v3.25.2
Consolidated Schedule of Investments (Parenthetical) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Mar. 31, 2025
Jun. 30, 2025
Jun. 30, 2024
Sep. 30, 2024
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     $ 8,235,411 $ 8,235,411    
Net realized gain (loss)       (41,844) $ (49,505)  
Investments, at fair value, ending balance $ 8,961,549 [2]     8,961,549 [2]   $ 8,235,411 [1]
Non-controlled affiliate company investments            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     211,382 [1],[3] 211,382 [1],[3] 87,084 87,084
Gross additions       76,511   177,905
Gross reductions       (21,110)   (37,747)
Net change in unrealized appreciation (depreciation)       457   4,600
Net realized gain (loss) 0 $ 0   0 (18,517) (20,460)
Investments, at fair value, ending balance 267,240 [2]     267,240 [2]   211,382 [1],[3]
Interest, dividend and fee income       8,188   9,448
Controlled affiliate company investments            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     12,205 [1] 12,205 [1] 12,790 12,790
Gross additions       362   11,979
Gross reductions       0   (11,344)
Net change in unrealized appreciation (depreciation)       (711)   10,406
Net realized gain (loss)       0   (11,626)
Investments, at fair value, ending balance 11,856 [2],[4]     11,856 [2],[4]   12,205 [1]
Interest, dividend and fee income       377   439
Investment, Identifier [Axis]: 3ES Innovation, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[7],[8]     25,451 25,451    
Investments, at fair value, ending balance [1],[5],[6],[7],[8]           25,451
Investment, Identifier [Axis]: 3ES Innovation, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8]     0 0    
Investments, at fair value, ending balance [1],[5],[7],[8]           0
Investment, Identifier [Axis]: AAH TOPCO, LLC , One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,672 8,672    
Investments, at fair value, ending balance [1],[5],[9]           8,672
Investment, Identifier [Axis]: AAH TOPCO, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 8,626     8,626    
Investment, Identifier [Axis]: AAH TOPCO, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     8,152 8,152    
Investments, at fair value, ending balance 8,110 [2],[10]     8,110 [2],[10]   8,152 [1],[5]
Investment, Identifier [Axis]: AAH TOPCO, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,483 1,483    
Investments, at fair value, ending balance 3,486 [2],[10]     3,486 [2],[10]   1,483 [1],[5]
Investment, Identifier [Axis]: AAH TOPCO, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: AAH TOPCO, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: AAH TOPCO, LLC, Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     2,566 2,566    
Investments, at fair value, ending balance 2,945 [2],[10],[15]     2,945 [2],[10],[15]   2,566 [1],[5],[14]
Investment, Identifier [Axis]: ACP Ulysses Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[16],[17],[18]     30,144 30,144    
Investments, at fair value, ending balance 30,144 [2],[10],[11]     30,144 [2],[10],[11]   30,144 [1],[6],[16],[17],[18]
Investment, Identifier [Axis]: ACP Ulysses Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[9]     1,303 1,303    
Investments, at fair value, ending balance 1,303 [2],[10],[11]     1,303 [2],[10],[11]   1,303 [1],[6],[9]
Investment, Identifier [Axis]: ADCS Clinics Intermediate Holdings, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: ADCS Clinics Intermediate Holdings, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,300 1,300    
Investments, at fair value, ending balance 1,170 [2],[10]     1,170 [2],[10]   1,300 [1],[5]
Investment, Identifier [Axis]: AI Titan Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     10,403 10,403    
Investments, at fair value, ending balance 10,508 [2],[10]     10,508 [2],[10]   10,403 [1],[5]
Investment, Identifier [Axis]: AI Titan Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (11) (11)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (11) [1],[5],[12]
Investment, Identifier [Axis]: AI Titan Parent, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (13) (13)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (13) [1],[5],[12]
Investment, Identifier [Axis]: ALKU Intermediate Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     6,882 6,882    
Investments, at fair value, ending balance 6,746 [2],[10]     6,746 [2],[10]   6,882 [1],[5],[9]
Investment, Identifier [Axis]: ALKU Intermediate Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     751 751    
Investments, at fair value, ending balance 731 [2],[10]     731 [2],[10]   751 [1],[5],[9]
Investment, Identifier [Axis]: AMBA Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     4,468 4,468    
Investments, at fair value, ending balance 4,434 [2],[10]     4,434 [2],[10]   4,468 [1],[5],[17]
Investment, Identifier [Axis]: AMBA Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,330 1,330    
Investments, at fair value, ending balance 1,320 [2],[10]     1,320 [2],[10]   1,330 [1],[5]
Investment, Identifier [Axis]: AMBA Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,122 1,122    
Investments, at fair value, ending balance 1,114 [2],[10]     1,114 [2],[10]   1,122 [1],[5],[9]
Investment, Identifier [Axis]: AMBA Buyer, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 161 [2],[10]     161 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: AMBA Buyer, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     162 162    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   162 [1],[5]
Investment, Identifier [Axis]: AP Adhesives Holdings, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (10)     (10)    
Investment, Identifier [Axis]: AP Adhesives Holdings, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 34     34    
Investment, Identifier [Axis]: AP Adhesives Holdings, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 5,771     5,771    
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     184 184    
Investments, at fair value, ending balance 134 [2],[10]     134 [2],[10]   184 [1],[5]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     6,419 6,419    
Investments, at fair value, ending balance 6,369 [2],[10],[11]     6,369 [2],[10],[11]   6,419 [1],[5],[16]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     5,365 5,365    
Investments, at fair value, ending balance 5,324 [2],[10],[20]     5,324 [2],[10],[20]   5,365 [1],[5],[19]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     837 837    
Investments, at fair value, ending balance 831 [2],[10]     831 [2],[10]   837 [1],[5]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     397 397    
Investments, at fair value, ending balance 393 [2],[10]     393 [2],[10]   397 [1],[5]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, Subordinated debt 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     15,672 15,672    
Investments, at fair value, ending balance 17,980 [2],[10],[15]     17,980 [2],[10],[15]   15,672 [1],[5],[14]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, Subordinated debt 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,400 3,400    
Investments, at fair value, ending balance 3,902 [2],[10],[15]     3,902 [2],[10],[15]   3,400 [1],[5],[14]
Investment, Identifier [Axis]: AVG Intermediate Holdings & AVG Subsidiary Holdings LLC, Subordinated debt 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,300 1,300    
Investments, at fair value, ending balance 1,492 [2],[10],[15]     1,492 [2],[10],[15]   1,300 [1],[5],[14]
Investment, Identifier [Axis]: Abita Brewing Co. LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     6,000 6,000 6,536 6,536
Gross additions       9,247   2,166
Gross reductions       (7,735)   (709)
Net change in unrealized appreciation (depreciation)       (1,055)   (1,993)
Net realized gain (loss)       0   0
Investments, at fair value, ending balance 6,457     6,457   6,000
Interest, dividend and fee income       78   575
Investment, Identifier [Axis]: Abita Brewing Co., L.L.C., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     4,888 4,888    
Investments, at fair value, ending balance 4,193 [2],[10],[15],[22]     4,193 [2],[10],[15],[22]   4,888 [1],[5],[14],[21]
Investment, Identifier [Axis]: Abita Brewing Co., L.L.C., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     677 677    
Investments, at fair value, ending balance 1,904 [2],[10],[15]     1,904 [2],[10],[15]   677 [1],[5],[14]
Investment, Identifier [Axis]: Abita Brewing Co., L.L.C., Second lien            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     435 435    
Investments, at fair value, ending balance 360 [2],[10],[15],[22]     360 [2],[10],[15],[22]   435 [1],[5],[14],[21]
Investment, Identifier [Axis]: Abita Brewing Co., L.L.C., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Accelya Lux Finco S.A.R.L., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[23]     8,547 8,547    
Investments, at fair value, ending balance 9,085 [2],[10],[15],[24],[25]     9,085 [2],[10],[15],[24],[25]   8,547 [1],[5],[8],[9],[14],[23]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[18],[19]     36,885 36,885    
Investments, at fair value, ending balance 36,779 [2],[10],[11],[20]     36,779 [2],[10],[11],[20]   36,885 [1],[5],[6],[16],[18],[19]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[19]     9,453 9,453    
Investments, at fair value, ending balance 9,426 [2],[10],[11],[20]     9,426 [2],[10],[11],[20]   9,453 [1],[5],[16],[19]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     8,319 8,319    
Investments, at fair value, ending balance 8,299 [2],[10],[11]     8,299 [2],[10],[11]   8,319 [1],[5],[17]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     5,223 5,223    
Investments, at fair value, ending balance 9,269 [2],[10]     9,269 [2],[10]   5,223 [1],[5],[9],[17]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (13) (13)    
Investments, at fair value, ending balance 7,793 [2],[10],[11]     7,793 [2],[10],[11]   (13) [1],[5],[12]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance 5,209 [2],[10],[11]     5,209 [2],[10],[11]   (3) [1],[5],[12]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,207 7,207    
Investments, at fair value, ending balance 1,316 [2],[10]     1,316 [2],[10]   7,207 [1],[5]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (111) (111)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (111) [1],[5],[12]
Investment, Identifier [Axis]: Accession Risk Management Group, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     9,988 9,988    
Investments, at fair value, ending balance 11,026 [2],[10],[27]     11,026 [2],[10],[27]   9,988 [1],[5],[26]
Investment, Identifier [Axis]: Acquia, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     12,020 12,020    
Investments, at fair value, ending balance 12,020 [2],[10],[11],[20]     12,020 [2],[10],[11],[20]   12,020 [1],[5],[19]
Investment, Identifier [Axis]: Acquia, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     44 44    
Investments, at fair value, ending balance 1,083 [2],[10]     1,083 [2],[10]   44 [1],[5]
Investment, Identifier [Axis]: Acquia, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,083 1,083    
Investments, at fair value, ending balance 112 [2],[10]     112 [2],[10]   1,083 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,217 1,217    
Investments, at fair value, ending balance 2,049 [2],[10]     2,049 [2],[10]   1,217 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     17,388 17,388    
Investments, at fair value, ending balance 17,254 [2],[10],[11]     17,254 [2],[10],[11]   17,388 [1],[5],[18]
Investment, Identifier [Axis]: Active Day, Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 6,611     6,611    
Investment, Identifier [Axis]: Active Day, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     1,343 1,343    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   1,343 [1],[5],[18]
Investment, Identifier [Axis]: Active Day, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[18]     865 865    
Investments, at fair value, ending balance 1,332 [2],[10]     1,332 [2],[10]   865 [1],[6],[18]
Investment, Identifier [Axis]: Active Day, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     689 689    
Investments, at fair value, ending balance 858 [2],[10]     858 [2],[10]   689 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     608 608    
Investments, at fair value, ending balance 684 [2],[10]     684 [2],[10]   608 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[18]     597 597    
Investments, at fair value, ending balance 604 [2],[10]     604 [2],[10]   597 [1],[6],[18]
Investment, Identifier [Axis]: Active Day, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 593 [2],[10]     593 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Active Day, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,614 4,614    
Investments, at fair value, ending balance 5,335 [2],[10]     5,335 [2],[10]   4,614 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,919 2,919    
Investments, at fair value, ending balance 3,421 [2],[10]     3,421 [2],[10]   2,919 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     16,177 16,177    
Investments, at fair value, ending balance 16,053 [2],[10]     16,053 [2],[10]   16,177 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     443 443    
Investments, at fair value, ending balance 441 [2],[10]     441 [2],[10]   443 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     279 279    
Investments, at fair value, ending balance 307 [2],[10],[15]     307 [2],[10],[15]   279 [1],[5],[14]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     212 212    
Investments, at fair value, ending balance 210 [2],[10]     210 [2],[10]   212 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     163 163    
Investments, at fair value, ending balance 162 [2],[10]     162 [2],[10]   163 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     109 109    
Investments, at fair value, ending balance 120 [2],[10],[15]     120 [2],[10],[15]   109 [1],[5],[14]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1 1    
Investments, at fair value, ending balance 1 [2],[10]     1 [2],[10]   1 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     14,733 14,733    
Investments, at fair value, ending balance 16,302 [2],[10],[15]     16,302 [2],[10],[15]   14,733 [1],[5],[14]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,996 3,996    
Investments, at fair value, ending balance 3,975 [2],[10]     3,975 [2],[10]   3,996 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,559 3,559    
Investments, at fair value, ending balance 3,540 [2],[10]     3,540 [2],[10]   3,559 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     3,504 3,504    
Investments, at fair value, ending balance 3,512 [2],[10],[11]     3,512 [2],[10],[11]   3,504 [1],[5],[18]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,138 3,138    
Investments, at fair value, ending balance 3,122 [2],[10]     3,122 [2],[10]   3,138 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,006 2,006    
Investments, at fair value, ending balance 1,991 [2],[10]     1,991 [2],[10]   2,006 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,829 1,829    
Investments, at fair value, ending balance 1,818 [2],[10]     1,818 [2],[10]   1,829 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,023 1,023    
Investments, at fair value, ending balance 1,015 [2],[10]     1,015 [2],[10]   1,023 [1],[5]
Investment, Identifier [Axis]: Acuity Eyecare Holdings, LLC, Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     108 108    
Investments, at fair value, ending balance 107 [2],[10]     107 [2],[10]   108 [1],[5]
Investment, Identifier [Axis]: Alegeus Technologies Holdings Corp., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     535 535    
Investments, at fair value, ending balance [1],[5]           535
Investment, Identifier [Axis]: Alera Group, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     35,416 35,416    
Investments, at fair value, ending balance [1],[5],[9],[19]           35,416
Investment, Identifier [Axis]: Alera Group, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     10,065 10,065    
Investments, at fair value, ending balance [1],[5],[17]           10,065
Investment, Identifier [Axis]: Alera Group, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     4,018 4,018    
Investments, at fair value, ending balance [1],[5],[17]           4,018
Investment, Identifier [Axis]: Alera Group, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,080 1,080    
Investments, at fair value, ending balance [1],[5]           1,080
Investment, Identifier [Axis]: Amalthea Parent, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     390 390    
Investments, at fair value, ending balance 408 [2],[10],[25],[28]     408 [2],[10],[25],[28]   390 [1],[5],[8]
Investment, Identifier [Axis]: Amalthea Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[8],[9],[16],[17],[18],[19]     82,385 82,385    
Investments, at fair value, ending balance 83,486 [2],[10],[11],[20],[25],[28]     83,486 [2],[10],[11],[20],[25],[28]   82,385 [1],[5],[6],[8],[9],[16],[17],[18],[19]
Investment, Identifier [Axis]: Amalthea Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     328 328    
Investments, at fair value, ending balance 520 [2],[10],[25],[28]     520 [2],[10],[25],[28]   328 [1],[5],[8]
Investment, Identifier [Axis]: Amberfield Acquisition Co., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     447 447    
Investments, at fair value, ending balance 452 [2],[10]     452 [2],[10]   447 [1],[5]
Investment, Identifier [Axis]: Amberfield Acquisition Co., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     4,866 4,866    
Investments, at fair value, ending balance 7,138 [2],[10],[11]     7,138 [2],[10],[11]   4,866 [1],[5],[9],[17]
Investment, Identifier [Axis]: Amberfield Acquisition Co., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 176 [2],[10]     176 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Amberfield Acquisition Co., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Anaplan, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,492 1,492    
Investments, at fair value, ending balance 1,498 [2],[10]     1,498 [2],[10]   1,492 [1],[5]
Investment, Identifier [Axis]: Anaplan, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     24,680 24,680    
Investments, at fair value, ending balance 58,468 [2],[10],[20]     58,468 [2],[10],[20]   24,680 [1],[5],[9],[19]
Investment, Identifier [Axis]: Anaplan, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     13,000 13,000    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   13,000 [1],[5]
Investment, Identifier [Axis]: Anaplan, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Any Hour, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     8,975 8,975    
Investments, at fair value, ending balance 8,458 [2],[11]     8,458 [2],[11]   8,975 [1],[5],[16]
Investment, Identifier [Axis]: Any Hour, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     2,847 2,847    
Investments, at fair value, ending balance 2,916 [2],[10],[15]     2,916 [2],[10],[15]   2,847 [1],[5],[14]
Investment, Identifier [Axis]: Any Hour, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     294 294    
Investments, at fair value, ending balance 455 [2],[10]     455 [2],[10]   294 [1],[5]
Investment, Identifier [Axis]: Any Hour, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     230 230    
Investments, at fair value, ending balance 240 [2],[10]     240 [2],[10]   230 [1],[5]
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,390 4,390    
Investments, at fair value, ending balance 13,877 [2],[10]     13,877 [2],[10]   4,390 [1],[5],[9]
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,406 1,406    
Investments, at fair value, ending balance 4,401 [2],[10]     4,401 [2],[10]   1,406 [1],[5]
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,045 1,045    
Investments, at fair value, ending balance 1,048 [2],[10]     1,048 [2],[10]   1,045 [1],[5]
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     38 38    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   38 [1],[5]
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,203     2,203    
Investment, Identifier [Axis]: Apex Service Partners, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,680     2,680    
Investment, Identifier [Axis]: Apothecary Products, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,321 2,321    
Investments, at fair value, ending balance 2,243 [2],[10]     2,243 [2],[10]   2,321 [1],[5]
Investment, Identifier [Axis]: Apothecary Products, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 39 [2],[10]     39 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Appfire Technologies, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[19]     55,159 55,159    
Investments, at fair value, ending balance 56,800 [2],[10],[11],[20]     56,800 [2],[10],[11],[20]   55,159 [1],[5],[16],[19]
Investment, Identifier [Axis]: Appfire Technologies, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,603 1,603    
Investments, at fair value, ending balance (5) [2],[10],[13]     (5) [2],[10],[13]   1,603 [1],[5]
Investment, Identifier [Axis]: Appfire Technologies, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (19) [2],[10],[13]     (19) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Appfire Technologies, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (266) [2],[10],[13]     (266) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Appriss Health Intermediate Holdings, Inc, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     3,777 3,777    
Investments, at fair value, ending balance [1],[5],[26]           3,777
Investment, Identifier [Axis]: Aras Corporation, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     531 531    
Investments, at fair value, ending balance 696 [2],[10]     696 [2],[10]   531 [1],[5]
Investment, Identifier [Axis]: Aras Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[19]     28,740 28,740    
Investments, at fair value, ending balance 28,523 [2],[10],[20]     28,523 [2],[10],[20]   28,740 [1],[5],[9],[14],[19]
Investment, Identifier [Axis]: Aras Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,217 1,217    
Investments, at fair value, ending balance 2,000 [2],[10]     2,000 [2],[10]   1,217 [1],[5]
Investment, Identifier [Axis]: Aras Corporation, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     2,108 2,108    
Investments, at fair value, ending balance 2,346 [2],[10],[27]     2,346 [2],[10],[27]   2,108 [1],[5],[26]
Investment, Identifier [Axis]: Arch Global CCT Holdings Corp., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[18]     3,128 3,128    
Investments, at fair value, ending balance 3,137 [2],[10],[11]     3,137 [2],[10],[11]   3,128 [1],[5],[9],[18]
Investment, Identifier [Axis]: Arch Global CCT Holdings Corp., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     629 629    
Investments, at fair value, ending balance 630 [2],[10]     630 [2],[10]   629 [1],[5],[9]
Investment, Identifier [Axis]: Arch Global CCT Holdings Corp., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     585 585    
Investments, at fair value, ending balance 586 [2],[10]     586 [2],[10]   585 [1],[5]
Investment, Identifier [Axis]: Arch Global CCT Holdings Corp., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     93 93    
Investments, at fair value, ending balance [1],[5]           93
Investment, Identifier [Axis]: Arctic Wolf Networks, Inc. and Arctic Wolf Networks Canada, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,470 7,470    
Investments, at fair value, ending balance 8,619 [2],[10]     8,619 [2],[10]   7,470 [1],[5]
Investment, Identifier [Axis]: Arctic Wolf Networks, Inc. and Arctic Wolf Networks Canada, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,959 1,959    
Investments, at fair value, ending balance 2,260 [2],[10]     2,260 [2],[10]   1,959 [1],[5]
Investment, Identifier [Axis]: Arctic Wolf Networks, Inc. and Arctic Wolf Networks Canada, Inc., Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     449 449    
Investments, at fair value, ending balance 519 [2],[10]     519 [2],[10]   449 [1],[5]
Investment, Identifier [Axis]: Arctic Wolf Networks, Inc. and Arctic Wolf Networks Canada, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,393 2,393    
Investments, at fair value, ending balance 2,815 [2],[10]     2,815 [2],[10]   2,393 [1],[5]
Investment, Identifier [Axis]: Armstrong Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     5,815 5,815    
Investments, at fair value, ending balance 5,970 [2],[10],[25],[31],[32]     5,970 [2],[10],[25],[31],[32]   5,815 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Armstrong Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     3,034 3,034    
Investments, at fair value, ending balance 3,115 [2],[10],[25],[31],[32]     3,115 [2],[10],[25],[31],[32]   3,034 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Arnott, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 355     355    
Investment, Identifier [Axis]: Arnott, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 4,700     4,700    
Investment, Identifier [Axis]: Arnott, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 126     126    
Investment, Identifier [Axis]: Arrow Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     25,104 25,104    
Investments, at fair value, ending balance 24,914 [2],[10]     24,914 [2],[10]   25,104 [1],[5],[9]
Investment, Identifier [Axis]: Arrow Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,645 1,645    
Investments, at fair value, ending balance 1,633 [2],[10]     1,633 [2],[10]   1,645 [1],[5]
Investment, Identifier [Axis]: Arrow Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,580 [2],[10]     1,580 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Artifact Bidco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,474 1,474    
Investments, at fair value, ending balance 1,489 [2],[10]     1,489 [2],[10]   1,474 [1],[5]
Investment, Identifier [Axis]: Artifact Bidco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (2) [1],[5],[12]
Investment, Identifier [Axis]: Artifact Bidco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (1) (1)    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   (1) [1],[5],[12]
Investment, Identifier [Axis]: Artifact Bidco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (1) (1)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (1) [1],[5],[12]
Investment, Identifier [Axis]: Aspen Medical Products, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     111 111    
Investments, at fair value, ending balance 96 [2],[10]     96 [2],[10]   111 [1],[5]
Investment, Identifier [Axis]: Aspen Medical Products, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[18]     5,013 5,013    
Investments, at fair value, ending balance 7,032 [2],[10],[11]     7,032 [2],[10],[11]   5,013 [1],[5],[16],[18]
Investment, Identifier [Axis]: Aspen Medical Products, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     321 321    
Investments, at fair value, ending balance 456 [2],[10]     456 [2],[10]   321 [1],[5],[9]
Investment, Identifier [Axis]: Aspen Medical Products, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5]
Investment, Identifier [Axis]: Aspen Medical Products, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 893     893    
Investment, Identifier [Axis]: Astute Holdings, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     547 547    
Investments, at fair value, ending balance 204 [2],[10]     204 [2],[10]   547 [1],[5]
Investment, Identifier [Axis]: Auvik Networks Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[28] 1,965     1,965    
Investment, Identifier [Axis]: Auvik Networks Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[14],[19]     10,663 10,663    
Investments, at fair value, ending balance 10,928 [2],[10],[15],[20],[25],[28]     10,928 [2],[10],[15],[20],[25],[28]   10,663 [1],[5],[7],[8],[14],[19]
Investment, Identifier [Axis]: Auvik Networks Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[14]     1,918 1,918    
Investments, at fair value, ending balance [1],[5],[7],[8],[9],[14]           1,918
Investment, Identifier [Axis]: Auvik Networks Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[14]     976 976    
Investments, at fair value, ending balance 1,001 [2],[10],[15],[25],[28]     1,001 [2],[10],[15],[25],[28]   976 [1],[5],[7],[8],[9],[14]
Investment, Identifier [Axis]: Auvik Networks Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[28]     0 [2],[10],[25],[28]   0 [1],[5],[7],[8]
Investment, Identifier [Axis]: Auvik Networks Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8]     504 504    
Investments, at fair value, ending balance 595 [2],[10],[25],[28]     595 [2],[10],[25],[28]   504 [1],[5],[7],[8]
Investment, Identifier [Axis]: Auvik Networks Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8]     57 57    
Investments, at fair value, ending balance 67 [2],[10],[25],[28]     67 [2],[10],[25],[28]   57 [1],[5],[7],[8]
Investment, Identifier [Axis]: Avalara, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     18,170 18,170    
Investments, at fair value, ending balance [1],[5],[9]           18,170
Investment, Identifier [Axis]: Avalara, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Ave Holdings III, Corp, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     936 936    
Investments, at fair value, ending balance 159 [2],[10]     159 [2],[10]   936 [1],[5]
Investment, Identifier [Axis]: Ave Holdings III, Corp, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9]     23,420 23,420    
Investments, at fair value, ending balance 22,775 [2],[10],[11]     22,775 [2],[10],[11]   23,420 [1],[5],[6],[9]
Investment, Identifier [Axis]: Ave Holdings III, Corp, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     6,108 6,108    
Investments, at fair value, ending balance 5,940 [2],[10]     5,940 [2],[10]   6,108 [1],[5],[17]
Investment, Identifier [Axis]: Ave Holdings III, Corp, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     802 802    
Investments, at fair value, ending balance 780 [2],[10]     780 [2],[10]   802 [1],[5]
Investment, Identifier [Axis]: Ave Holdings III, Corp, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (6) [2],[10],[13]     (6) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Ave Holdings III, Corp, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     17,541 17,541    
Investments, at fair value, ending balance 17,377 [2],[10],[27]     17,377 [2],[10],[27]   17,541 [1],[5],[26]
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     6,666 6,666    
Investments, at fair value, ending balance [1],[5],[9]           6,666
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30]     2,743 2,743    
Investments, at fair value, ending balance [1],[5],[8],[30]           2,743
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,209 1,209    
Investments, at fair value, ending balance [1],[5],[9]           1,209
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     174 174    
Investments, at fair value, ending balance [1],[5]           174
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Axiom Merger Sub Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (98) (98)    
Investments, at fair value, ending balance [1],[5],[12]           (98)
Investment, Identifier [Axis]: Azul Systems, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16]     9,492 9,492    
Investments, at fair value, ending balance 9,492 [2],[11]     9,492 [2],[11]   9,492 [1],[16]
Investment, Identifier [Axis]: Azul Systems, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Azurite Intermediate Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     622 622    
Investments, at fair value, ending balance 973 [2],[10]     973 [2],[10]   622 [1],[5]
Investment, Identifier [Axis]: Azurite Intermediate Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     428 428    
Investments, at fair value, ending balance 428 [2],[10]     428 [2],[10]   428 [1],[5],[9]
Investment, Identifier [Axis]: Azurite Intermediate Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: BECO Holding Company, Inc., LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     987 987    
Investments, at fair value, ending balance [1],[5]           987
Investment, Identifier [Axis]: BECO Holding Company, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 928     928    
Investment, Identifier [Axis]: BECO Holding Company, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17],[18]     40,999 40,999    
Investments, at fair value, ending balance 40,479 [2],[10],[11]     40,479 [2],[10],[11]   40,999 [1],[5],[9],[16],[17],[18]
Investment, Identifier [Axis]: BECO Holding Company, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (4) [2],[10],[13]     (4) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: BECO Holding Company, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     17,976 17,976    
Investments, at fair value, ending balance 20,001 [2],[10],[27]     20,001 [2],[10],[27]   17,976 [1],[5],[26]
Investment, Identifier [Axis]: BHG Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 24,577     24,577    
Investment, Identifier [Axis]: BHG Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (27)     (27)    
Investment, Identifier [Axis]: BHG Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (62)     (62)    
Investment, Identifier [Axis]: BJH Holdings III Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17]     69,940 69,940    
Investments, at fair value, ending balance 69,929 [2],[10],[11]     69,929 [2],[10],[11]   69,940 [1],[5],[9],[16],[17]
Investment, Identifier [Axis]: BJH Holdings III Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     666 666    
Investments, at fair value, ending balance 5,575 [2],[10]     5,575 [2],[10]   666 [1],[5]
Investment, Identifier [Axis]: BJH Holdings III Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 351     351    
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     7,638 7,638    
Investments, at fair value, ending balance 7,745 [2],[10],[25],[31]     7,745 [2],[10],[25],[31]   7,638 [1],[5],[8],[29]
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     4,550 4,550    
Investments, at fair value, ending balance 4,881 [2],[10],[25],[31],[32]     4,881 [2],[10],[25],[31],[32]   4,550 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     1,886 1,886    
Investments, at fair value, ending balance 1,912 [2],[10],[25],[31]     1,912 [2],[10],[25],[31]   1,886 [1],[5],[8],[29]
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     1,334 1,334    
Investments, at fair value, ending balance 1,389 [2],[10],[25],[31],[32]     1,389 [2],[10],[25],[31],[32]   1,334 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     1,086 1,086    
Investments, at fair value, ending balance 1,164 [2],[10],[25],[31],[32]     1,164 [2],[10],[25],[31],[32]   1,086 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Baduhenna Bidco Limited, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     537 537    
Investments, at fair value, ending balance 1,231 [2],[10],[25],[31],[32]     1,231 [2],[10],[25],[31],[32]   537 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Baker Tilly Advisory Group, LP, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,301 3,301    
Investments, at fair value, ending balance 3,782 [2],[10]     3,782 [2],[10]   3,301 [1],[5]
Investment, Identifier [Axis]: Baker Tilly Advisory Group, LP, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (14) [2],[10],[13]     (14) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Baker Tilly Advisory Group, LP, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 4,675 [2],[10]     4,675 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Baker Tilly Advisory Group, LP, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (20)     (20)    
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     2,689 2,689    
Investments, at fair value, ending balance 2,719 [2],[10]     2,719 [2],[10]   2,689 [1],[5],[9],[14]
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30]     1,863 1,863    
Investments, at fair value, ending balance 1,993 [2],[10],[25],[32]     1,993 [2],[10],[25],[32]   1,863 [1],[5],[8],[9],[14],[30]
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     197 197    
Investments, at fair value, ending balance 416 [2],[10]     416 [2],[10]   197 [1],[5],[14]
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance 128 [2],[10]     128 [2],[10]   (4) [1],[5],[12]
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Bamboo US Bidco LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Banker's Toolbox, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     20,569 20,569    
Investments, at fair value, ending balance 20,411 [2],[10],[11]     20,411 [2],[10],[11]   20,569 [1],[5],[17]
Investment, Identifier [Axis]: Banker's Toolbox, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Barteca Restaurants, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[18]     13,680 13,680    
Investments, at fair value, ending balance 13,575 [2],[10],[11]     13,575 [2],[10],[11]   13,680 [1],[5],[16],[18]
Investment, Identifier [Axis]: Barteca Restaurants, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     690 690    
Investments, at fair value, ending balance 684 [2],[10]     684 [2],[10]   690 [1],[5]
Investment, Identifier [Axis]: Barteca Restaurants, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     471 471    
Investments, at fair value, ending balance 468 [2],[10]     468 [2],[10]   471 [1],[5]
Investment, Identifier [Axis]: Barteca Restaurants, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     40 40    
Investments, at fair value, ending balance 200 [2],[10]     200 [2],[10]   40 [1],[5]
Investment, Identifier [Axis]: Batteries Plus Holding Corporation, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,239 1,239    
Investments, at fair value, ending balance 1,386 [2],[10]     1,386 [2],[10]   1,239 [1],[5]
Investment, Identifier [Axis]: Baxter Planning Systems, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     4,060 4,060    
Investments, at fair value, ending balance 4,164 [2],[10],[15]     4,164 [2],[10],[15]   4,060 [1],[5],[9],[14]
Investment, Identifier [Axis]: Baxter Planning Systems, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Baxter Planning Systems, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Bayshore Intermediate #2, L.P., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6,231 6,231    
Investments, at fair value, ending balance 7,322 [2],[10]     7,322 [2],[10]   6,231 [1],[5]
Investment, Identifier [Axis]: Bayshore Intermediate #2, L.P., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     117,557 117,557    
Investments, at fair value, ending balance 122,707 [2],[10],[15],[20]     122,707 [2],[10],[15],[20]   117,557 [1],[5],[14],[19]
Investment, Identifier [Axis]: Bayshore Intermediate #2, L.P., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 46 [2],[10]     46 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Bayside Opco, LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     29,127 29,127 22,044 22,044
Gross additions       863   2,758
Gross reductions       (119)   (699)
Net change in unrealized appreciation (depreciation)       2,345   5,024
Net realized gain (loss)       0   0
Investments, at fair value, ending balance 32,216     32,216   29,127
Interest, dividend and fee income       2,437   3,660
Investment, Identifier [Axis]: Bayside Opco, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6,788 6,788    
Investments, at fair value, ending balance 9,321 [2],[10]     9,321 [2],[10]   6,788 [1],[5]
Investment, Identifier [Axis]: Bayside Opco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     12,845 12,845    
Investments, at fair value, ending balance 12,758 [2],[10]     12,758 [2],[10]   12,845 [1],[5],[14]
Investment, Identifier [Axis]: Bayside Opco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     4,499 4,499    
Investments, at fair value, ending balance 4,513 [2],[10]     4,513 [2],[10]   4,499 [1],[5],[14]
Investment, Identifier [Axis]: Bayside Opco, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Bayside Opco, LLC, Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     4,995 4,995    
Investments, at fair value, ending balance 5,624 [2],[10],[15]     5,624 [2],[10],[15]   4,995 [1],[5],[14]
Investment, Identifier [Axis]: Bellwether Buyer, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (3)     (3)    
Investment, Identifier [Axis]: Bellwether Buyer, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 5,019     5,019    
Investment, Identifier [Axis]: Bellwether Buyer, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (7)     (7)    
Investment, Identifier [Axis]: Belmont Instrument, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[17],[18]     14,504 14,504    
Investments, at fair value, ending balance 14,393 [2],[10],[11]     14,393 [2],[10],[11]   14,504 [1],[6],[17],[18]
Investment, Identifier [Axis]: Belmont Instrument, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     66 66    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   66 [1],[5]
Investment, Identifier [Axis]: Ben Nevis Midco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     561 561    
Investments, at fair value, ending balance 561 [2],[10],[25],[31]     561 [2],[10],[25],[31]   561 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Ben Nevis Midco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     378 378    
Investments, at fair value, ending balance 378 [2],[10],[25],[31]     378 [2],[10],[25],[31]   378 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Ben Nevis Midco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     60 60    
Investments, at fair value, ending balance 465 [2],[10],[25],[31]     465 [2],[10],[25],[31]   60 [1],[5],[8],[29]
Investment, Identifier [Axis]: Ben Nevis Midco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     92 92    
Investments, at fair value, ending balance 97 [2],[10],[25],[31]     97 [2],[10],[25],[31]   92 [1],[5],[8],[29]
Investment, Identifier [Axis]: Benefit Plan Administrators of Eau Claire, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11] 13,005     13,005    
Investment, Identifier [Axis]: Benefit Plan Administrators of Eau Claire, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 9,975     9,975    
Investment, Identifier [Axis]: Benefit Plan Administrators of Eau Claire, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Benefit Plan Administrators of Eau Claire, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Benetech, Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     1,793 1,793    
Gross additions       347    
Gross reductions       (538)    
Net change in unrealized appreciation (depreciation)       519    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 2,121     2,121   1,793
Interest, dividend and fee income       8    
Investment, Identifier [Axis]: Benetech, Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     1,793 1,793 1,353 1,353
Gross additions           780
Gross reductions           (843)
Net change in unrealized appreciation (depreciation)           503
Net realized gain (loss)           0
Investments, at fair value, ending balance           1,793
Interest, dividend and fee income           9
Investment, Identifier [Axis]: Benetech, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     1,626 1,626    
Investments, at fair value, ending balance 2,019 [2],[10],[15],[22]     2,019 [2],[10],[15],[22]   1,626 [1],[5],[14],[21]
Investment, Identifier [Axis]: Benetech, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     167 167    
Investments, at fair value, ending balance 102 [2],[10],[15],[22]     102 [2],[10],[15],[22]   167 [1],[5],[14],[21]
Investment, Identifier [Axis]: BestPass, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     52,602 52,602    
Investments, at fair value, ending balance 52,470 [2],[10],[11]     52,470 [2],[10],[11]   52,602 [1],[5]
Investment, Identifier [Axis]: BestPass, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (26) (26)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (26) [1],[5],[12]
Investment, Identifier [Axis]: BestPass, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (35) (35)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (35) [1],[5],[12]
Investment, Identifier [Axis]: Biscuit Parent, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,332 1,332    
Investments, at fair value, ending balance 20,055 [2],[10],[11]     20,055 [2],[10],[11]   1,332 [1],[5],[9]
Investment, Identifier [Axis]: Biscuit Parent, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Biscuit Parent, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Blackbird Purchaser, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,476 4,476    
Investments, at fair value, ending balance 4,443 [2],[10]     4,443 [2],[10]   4,476 [1],[5],[9]
Investment, Identifier [Axis]: Blackbird Purchaser, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     265 265    
Investments, at fair value, ending balance 492 [2],[10]     492 [2],[10]   265 [1],[5]
Investment, Identifier [Axis]: Blackbird Purchaser, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     15 15    
Investments, at fair value, ending balance 50 [2],[10]     50 [2],[10]   15 [1],[5]
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[18]     12,285 12,285    
Investments, at fair value, ending balance 12,191 [2],[10],[11]     12,191 [2],[10],[11]   12,285 [1],[5],[9],[16],[18]
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,743 1,743    
Investments, at fair value, ending balance 1,729 [2],[10],[11]     1,729 [2],[10],[11]   1,743 [1],[5],[9]
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,409 1,409    
Investments, at fair value, ending balance 1,398 [2],[10]     1,398 [2],[10]   1,409 [1],[5],[9]
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     58 58    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   58 [1],[5]
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,280     2,280    
Investment, Identifier [Axis]: Blades Buyer, Inc., Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,726     1,726    
Investment, Identifier [Axis]: Blast Bidco Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,905 4,905    
Investments, at fair value, ending balance 4,867 [2],[10]     4,867 [2],[10]   4,905 [1],[5],[9]
Investment, Identifier [Axis]: Blast Bidco Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Bloomerang, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,142 4,142    
Investments, at fair value, ending balance 4,142 [2],[10]     4,142 [2],[10]   4,142 [1],[5],[9]
Investment, Identifier [Axis]: Bloomerang, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 414 [2],[10]     414 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Bloomerang, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 30 [2],[10]     30 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Blue Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 5,307     5,307    
Investment, Identifier [Axis]: Blue Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 9,370     9,370    
Investment, Identifier [Axis]: Blue Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31],[32] (46)     (46)    
Investment, Identifier [Axis]: Blue Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 1,325     1,325    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     856 856    
Investments, at fair value, ending balance 778 [2],[10]     778 [2],[10]   856 [1],[5]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[17],[18]     62,942 62,942    
Investments, at fair value, ending balance 12 [2],[10]     12 [2],[10]   62,942 [1],[5],[6],[16],[17],[18]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 414 [2],[10]     414 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 150     150    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 293     293    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 298     298    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 257     257    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 226     226    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1     1    
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     12,462 12,462    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   12,462 [1],[5],[9]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,905 2,905    
Investments, at fair value, ending balance 62,451 [2],[10],[11]     62,451 [2],[10],[11]   2,905 [1],[5],[9]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,793 2,793    
Investments, at fair value, ending balance 12,366 [2],[10]     12,366 [2],[10]   2,793 [1],[5],[9]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,765 2,765    
Investments, at fair value, ending balance 2,883 [2],[10]     2,883 [2],[10]   2,765 [1],[5]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,125 2,125    
Investments, at fair value, ending balance 2,771 [2],[10]     2,771 [2],[10]   2,125 [1],[5]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,258 1,258    
Investments, at fair value, ending balance 2,745 [2],[10]     2,745 [2],[10]   1,258 [1],[5]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     417 417    
Investments, at fair value, ending balance 2,109 [2],[10]     2,109 [2],[10]   417 [1],[5]
Investment, Identifier [Axis]: Blue River Pet Care, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     150 150    
Investments, at fair value, ending balance 1,249 [2],[10]     1,249 [2],[10]   150 [1],[5]
Investment, Identifier [Axis]: BlueMatrix Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     2,540 2,540    
Investments, at fair value, ending balance 2,520 [2],[10]     2,520 [2],[10]   2,540 [1],[5],[16]
Investment, Identifier [Axis]: BlueMatrix Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 9,950 [2],[10]     9,950 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: BlueMatrix Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: BlueMatrix Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 275     275    
Investment, Identifier [Axis]: Bonterra LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     91,501 91,501    
Investments, at fair value, ending balance [1],[5],[9],[19]           91,501
Investment, Identifier [Axis]: Bonterra LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,485 7,485    
Investments, at fair value, ending balance [1],[5]           7,485
Investment, Identifier [Axis]: Bonterra LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,778 3,778    
Investments, at fair value, ending balance [1],[5],[14]           3,778
Investment, Identifier [Axis]: Bonterra LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     226 226    
Investments, at fair value, ending balance [1],[5]           226
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4 4    
Investments, at fair value, ending balance 4 [2],[10]     4 [2],[10]   4 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     11 11    
Investments, at fair value, ending balance 11 [2],[10]     11 [2],[10]   11 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1 1    
Investments, at fair value, ending balance 1 [2],[10]     1 [2],[10]   1 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     18,823 18,823    
Investments, at fair value, ending balance 18,823 [2],[10],[20]     18,823 [2],[10],[20]   18,823 [1],[5],[19]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,556 1,556    
Investments, at fair value, ending balance 1,556 [2],[10]     1,556 [2],[10]   1,556 [1],[5],[9]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     231 231    
Investments, at fair value, ending balance 231 [2],[10]     231 [2],[10]   231 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     302 302    
Investments, at fair value, ending balance 288 [2],[10]     288 [2],[10]   302 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     15 15    
Investments, at fair value, ending balance 15 [2],[10]     15 [2],[10]   15 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6 6    
Investments, at fair value, ending balance 5 [2],[10]     5 [2],[10]   6 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Preferred stock 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4 4    
Investments, at fair value, ending balance 4 [2],[10]     4 [2],[10]   4 [1],[5]
Investment, Identifier [Axis]: Borrower R365 Holdings, LLC, Preferred stock 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     68 68    
Investments, at fair value, ending balance 64 [2],[10]     64 [2],[10]   68 [1],[5]
Investment, Identifier [Axis]: Bottomline Technologies, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     40,652 40,652    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   40,652 [1],[5],[9]
Investment, Identifier [Axis]: Bottomline Technologies, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,112 5,112    
Investments, at fair value, ending balance 45,811 [2],[10]     45,811 [2],[10]   5,112 [1],[5],[9]
Investment, Identifier [Axis]: Bottomline Technologies, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (6) (6)    
Investments, at fair value, ending balance [1],[5],[12]           (6)
Investment, Identifier [Axis]: BradyIFS Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     4,842 4,842    
Investments, at fair value, ending balance [1],[5],[19]           4,842
Investment, Identifier [Axis]: BradyIFS Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     382 382    
Investments, at fair value, ending balance [1],[5]           382
Investment, Identifier [Axis]: BradyIFS Holdings, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[20] 5,183     5,183    
Investment, Identifier [Axis]: BradyIFS Holdings, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 50     50    
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17]     77,997 77,997    
Investments, at fair value, ending balance 77,217 [2],[10],[11]     77,217 [2],[10],[11]   77,997 [1],[5],[16],[17]
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16]     3,190 3,190    
Investments, at fair value, ending balance 3,158 [2],[10],[11]     3,158 [2],[10],[11]   3,190 [1],[9],[16]
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     1,643 1,643    
Investments, at fair value, ending balance 1,627 [2],[10]     1,627 [2],[10]   1,643 [1],[5],[17]
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     736 736    
Investments, at fair value, ending balance 729 [2],[10]     729 [2],[10]   736 [1],[5],[9]
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     587 587    
Investments, at fair value, ending balance 581 [2],[10]     581 [2],[10]   587 [1],[5],[9]
Investment, Identifier [Axis]: Bullhorn, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (5) [2],[10],[13]     (5) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Burning Glass Intermediate Holdings Company, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[18]     12,431 12,431    
Investments, at fair value, ending balance 11,232 [2],[11]     11,232 [2],[11]   12,431 [1],[5],[16],[18]
Investment, Identifier [Axis]: Burning Glass Intermediate Holdings Company, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 154 [2],[10]     154 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Bynder BidCo, Inc.& Bynder BidCo B.V., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[33]     8,332 8,332    
Investments, at fair value, ending balance 8,332 [2],[10],[25],[34]     8,332 [2],[10],[25],[34]   8,332 [1],[5],[8],[9],[33]
Investment, Identifier [Axis]: Bynder BidCo, Inc.& Bynder BidCo B.V., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[33]     2,204 2,204    
Investments, at fair value, ending balance 2,204 [2],[10],[25],[34]     2,204 [2],[10],[25],[34]   2,204 [1],[5],[8],[9],[33]
Investment, Identifier [Axis]: Bynder BidCo, Inc.& Bynder BidCo B.V., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[33]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[34]     0 [2],[10],[25],[34]   0 [1],[5],[8],[33]
Investment, Identifier [Axis]: Bynder BidCo, Inc.& Bynder BidCo B.V., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[33]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[34]     0 [2],[10],[13],[25],[34]   0 [1],[5],[8],[12],[33]
Investment, Identifier [Axis]: CAP-KSI Holdings, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 125 [2],[10]     125 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: CAP-KSI Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6,584 6,584    
Investments, at fair value, ending balance 11,230 [2],[10],[11]     11,230 [2],[10],[11]   6,584 [1],[5]
Investment, Identifier [Axis]: CAP-KSI Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     182 182    
Investments, at fair value, ending balance 825 [2],[10]     825 [2],[10]   182 [1],[5]
Investment, Identifier [Axis]: CAP-KSI Holdings, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     645 645    
Investments, at fair value, ending balance 702 [2],[10]     702 [2],[10]   645 [1],[5]
Investment, Identifier [Axis]: CB Buyer, Inc., LP Units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     258 258    
Investments, at fair value, ending balance [1],[5]           258
Investment, Identifier [Axis]: CB Buyer, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 176     176    
Investment, Identifier [Axis]: CB Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     46,611 46,611    
Investments, at fair value, ending balance 50,076 [2],[10]     50,076 [2],[10]   46,611 [1],[5]
Investment, Identifier [Axis]: CB Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: CB Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,520 [2],[10]     1,520 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: CCSL Holdings, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     680 680    
Investments, at fair value, ending balance 577 [2],[10],[25]     577 [2],[10],[25]   680 [1],[5],[8]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[8],[16],[18]     20,903 20,903    
Investments, at fair value, ending balance 20,897 [2],[11],[25]     20,897 [2],[11],[25]   20,903 [1],[6],[8],[16],[18]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25] 2,774     2,774    
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25] 2,207     2,207    
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9]     5,642 5,642    
Investments, at fair value, ending balance 5,642 [2],[10],[11],[25]     5,642 [2],[10],[11],[25]   5,642 [1],[5],[8],[9]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[30]     3,552 3,552    
Investments, at fair value, ending balance 3,646 [2],[10],[25],[32]     3,646 [2],[10],[25],[32]   3,552 [1],[5],[8],[9],[30]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     3,472 3,472    
Investments, at fair value, ending balance 3,472 [2],[10],[25]     3,472 [2],[10],[25]   3,472 [1],[5],[8]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     2,884 2,884    
Investments, at fair value, ending balance 2,884 [2],[10],[11],[25]     2,884 [2],[10],[11],[25]   2,884 [1],[5],[8]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     116 116    
Investments, at fair value, ending balance 80 [2],[10],[25]     80 [2],[10],[25]   116 [1],[5],[8]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12]     (7) (7)    
Investments, at fair value, ending balance 977 [2],[10],[25]     977 [2],[10],[25]   (7) [1],[5],[8],[12]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30]     (247) (247)    
Investments, at fair value, ending balance 34,629 [2],[10],[25],[32]     34,629 [2],[10],[25],[32]   (247) [1],[5],[8],[12],[30]
Investment, Identifier [Axis]: CCSL Holdings, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30]     (48) (48)    
Investments, at fair value, ending balance 6,784 [2],[10],[25],[32]     6,784 [2],[10],[25],[32]   (48) [1],[5],[8],[12],[30]
Investment, Identifier [Axis]: CG Group Holdings, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     645 645    
Investments, at fair value, ending balance 883 [2],[10]     883 [2],[10]   645 [1],[5]
Investment, Identifier [Axis]: CG Group Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[14],[16],[18]     45,452 45,452    
Investments, at fair value, ending balance 46,270 [2],[10],[11],[15]     46,270 [2],[10],[11],[15]   45,452 [1],[5],[6],[9],[14],[16],[18]
Investment, Identifier [Axis]: CG Group Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     698 698    
Investments, at fair value, ending balance 800 [2],[10],[15]     800 [2],[10],[15]   698 [1],[5],[14]
Investment, Identifier [Axis]: CHA Vision Holdings, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 544     544    
Investment, Identifier [Axis]: CHA Vision Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,061     1,061    
Investment, Identifier [Axis]: CHA Vision Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 208     208    
Investment, Identifier [Axis]: CHA Vision Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: CHHJ Midco, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     419 419    
Investments, at fair value, ending balance 456 [2],[10],[27]     456 [2],[10],[27]   419 [1],[5],[26]
Investment, Identifier [Axis]: CHHJ Midco, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     3,732 3,732    
Investments, at fair value, ending balance 3,702 [2],[10],[11]     3,702 [2],[10],[11]   3,732 [1],[16],[18]
Investment, Identifier [Axis]: CHHJ Midco, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, Common Stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     301 301    
Investments, at fair value, ending balance [1],[5]           301
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 439     439    
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     2,945 2,945    
Investments, at fair value, ending balance 6,367 [2],[10],[11]     6,367 [2],[10],[11]   2,945 [1],[5],[16]
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,371 1,371    
Investments, at fair value, ending balance 1,656 [2],[10]     1,656 [2],[10]   1,371 [1],[5]
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: CHVAC Services Investment, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 61     61    
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC, LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     996 996    
Investments, at fair value, ending balance [1],[5]           996
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 962     962    
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16]     27,427 27,427    
Investments, at fair value, ending balance [1],[5],[9],[16]           27,427
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     53 53    
Investments, at fair value, ending balance [1],[5]           53
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 30,327     30,327    
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 75     75    
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 683     683    
Investment, Identifier [Axis]: CI (Quercus) Intermediate Holdings, LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (5)     (5)    
Investment, Identifier [Axis]: CMI Parent Inc., Common stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     626 626    
Investments, at fair value, ending balance 664 [2],[10]     664 [2],[10]   626 [1],[5]
Investment, Identifier [Axis]: CMI Parent Inc., Common stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     716 716    
Investments, at fair value, ending balance 909 [2],[10]     909 [2],[10]   716 [1],[5]
Investment, Identifier [Axis]: CMI Parent Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     22,468 22,468    
Investments, at fair value, ending balance 22,412 [2],[11]     22,412 [2],[11]   22,468 [1],[5]
Investment, Identifier [Axis]: CMI Parent Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[19]     19,789 19,789    
Investments, at fair value, ending balance 19,732 [2],[11],[20]     19,732 [2],[11],[20]   19,789 [1],[5],[16],[19]
Investment, Identifier [Axis]: CMI Parent Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,899 8,899    
Investments, at fair value, ending balance 8,875 [2],[10],[11]     8,875 [2],[10],[11]   8,899 [1],[5],[9]
Investment, Identifier [Axis]: CMI Parent Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance [1],[5],[12]           (3)
Investment, Identifier [Axis]: CMI Parent Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: CMI Parent Inc., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11],[20] 9,460     9,460    
Investment, Identifier [Axis]: CMI Parent Inc., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     9,485 9,485    
Investments, at fair value, ending balance [1],[5],[19]           9,485
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,400 2,400    
Investments, at fair value, ending balance 5,504 [2],[10]     5,504 [2],[10]   2,400 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     922 922    
Investments, at fair value, ending balance 691 [2],[10]     691 [2],[10]   922 [1],[5]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,339 2,339    
Investments, at fair value, ending balance 2,381 [2],[10]     2,381 [2],[10]   2,339 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,533 1,533    
Investments, at fair value, ending balance 2,321 [2],[10]     2,321 [2],[10]   1,533 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,083 1,083    
Investments, at fair value, ending balance 1,520 [2],[10]     1,520 [2],[10]   1,083 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,154 1,154    
Investments, at fair value, ending balance 1,373 [2],[10]     1,373 [2],[10]   1,154 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     696 696    
Investments, at fair value, ending balance 1,146 [2],[10]     1,146 [2],[10]   696 [1],[5],[9]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,075 [2],[10]     1,075 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,383 1,383    
Investments, at fair value, ending balance 1,039 [2],[10]     1,039 [2],[10]   1,383 [1],[5]
Investment, Identifier [Axis]: COP Hometown Acquisitions, Inc., Senior secured 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,045 1,045    
Investments, at fair value, ending balance 915 [2],[10]     915 [2],[10]   1,045 [1],[5],[9]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     625 625    
Investments, at fair value, ending balance 853 [2],[10]     853 [2],[10]   625 [1],[5]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     23,379 23,379    
Investments, at fair value, ending balance 23,233 [2],[10],[11]     23,233 [2],[10],[11]   23,379 [1],[5],[9]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16]     6,318 6,318    
Investments, at fair value, ending balance 6,270 [2],[10],[11]     6,270 [2],[10],[11]   6,318 [1],[9],[16]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     5,667 5,667    
Investments, at fair value, ending balance 5,623 [2],[10],[11]     5,623 [2],[10],[11]   5,667 [1],[5],[16]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,281 4,281    
Investments, at fair value, ending balance 4,247 [2],[10],[11]     4,247 [2],[10],[11]   4,281 [1],[5],[9]
Investment, Identifier [Axis]: CRH Healthcare Purchaser, Inc., Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     240 240    
Investments, at fair value, ending balance 105 [2],[10]     105 [2],[10]   240 [1],[5]
Investment, Identifier [Axis]: CST Holding Company, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[17]     34,063 34,063    
Investments, at fair value, ending balance 33,802 [2],[10]     33,802 [2],[10]   34,063 [1],[9],[17]
Investment, Identifier [Axis]: CST Holding Company, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: CVP Holdco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     13,529 13,529    
Investments, at fair value, ending balance 13,529 [2],[10]     13,529 [2],[10]   13,529 [1],[5]
Investment, Identifier [Axis]: CVP Holdco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 736 [2],[10]     736 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: CVP Holdco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Caerus Midco 3 S.A.R.L., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[23]     29,117 29,117    
Investments, at fair value, ending balance 29,185 [2],[10],[11],[25]     29,185 [2],[10],[11],[25]   29,117 [1],[5],[8],[9],[23]
Investment, Identifier [Axis]: Caerus Midco 3 S.A.R.L., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[23]     4,827 4,827    
Investments, at fair value, ending balance 4,839 [2],[10],[25]     4,839 [2],[10],[25]   4,827 [1],[5],[8],[9],[23]
Investment, Identifier [Axis]: Caerus Midco 3 S.A.R.L., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[23]     1,941 1,941    
Investments, at fair value, ending balance 4,465 [2],[10],[25]     4,465 [2],[10],[25]   1,941 [1],[5],[8],[23]
Investment, Identifier [Axis]: Caerus Midco 3 S.A.R.L., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[23]     308 308    
Investments, at fair value, ending balance 708 [2],[10],[25]     708 [2],[10],[25]   308 [1],[5],[8],[23]
Investment, Identifier [Axis]: Caerus Midco 3 S.A.R.L., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[23]     256 256    
Investments, at fair value, ending balance 108 [2],[10],[25]     108 [2],[10],[25]   256 [1],[5],[8],[23]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc. Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     760 760    
Investments, at fair value, ending balance [1],[5]           760
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 602     602    
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[18]     17,827 17,827    
Investments, at fair value, ending balance 17,683 [2],[10],[11]     17,683 [2],[10],[11]   17,827 [1],[5],[6],[18]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     96 96    
Investments, at fair value, ending balance 95 [2],[10]     95 [2],[10]   96 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     78 78    
Investments, at fair value, ending balance 77 [2],[10]     77 [2],[10]   78 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     49 49    
Investments, at fair value, ending balance 49 [2],[10]     49 [2],[10]   49 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (1) (1)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (1) [1],[5],[12]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     3,178 3,178    
Investments, at fair value, ending balance 3,153 [2],[10],[11]     3,153 [2],[10],[11]   3,178 [1],[5],[18]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     2,135 2,135    
Investments, at fair value, ending balance 2,118 [2],[10],[11]     2,118 [2],[10],[11]   2,135 [1],[5],[18]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[18]     1,355 1,355    
Investments, at fair value, ending balance 1,344 [2],[11]     1,344 [2],[11]   1,355 [1],[6],[18]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18]     1,196 1,196    
Investments, at fair value, ending balance 1,187 [2],[10],[11]     1,187 [2],[10],[11]   1,196 [1],[5],[18]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     185 185    
Investments, at fair value, ending balance 161 [2],[10]     161 [2],[10]   185 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     171 171    
Investments, at fair value, ending balance 170 [2],[10]     170 [2],[10]   171 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     123 123    
Investments, at fair value, ending balance 122 [2],[10]     122 [2],[10]   123 [1],[5]
Investment, Identifier [Axis]: Cafe Rio Holding, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     98 98    
Investments, at fair value, ending balance 97 [2],[10]     97 [2],[10]   98 [1],[5]
Investment, Identifier [Axis]: Calabrio, Inc., LP interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,135 1,135    
Investments, at fair value, ending balance 1,168 [2],[10]     1,168 [2],[10]   1,135 [1],[5]
Investment, Identifier [Axis]: Calabrio, Inc., LP interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Calabrio, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     74,669 74,669    
Investments, at fair value, ending balance 74,108 [2],[10],[20]     74,108 [2],[10],[20]   74,669 [1],[5],[9],[19]
Investment, Identifier [Axis]: Calabrio, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,487 5,487    
Investments, at fair value, ending balance 5,445 [2],[10]     5,445 [2],[10]   5,487 [1],[5],[9]
Investment, Identifier [Axis]: Calabrio, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 202 [2],[10]     202 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Camelia Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     5,411 5,411    
Investments, at fair value, ending balance 5,555 [2],[10],[25],[31],[32]     5,555 [2],[10],[25],[31],[32]   5,411 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Camelia Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     766 766    
Investments, at fair value, ending balance 787 [2],[10],[25],[31],[32]     787 [2],[10],[25],[31],[32]   766 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Camelia Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     346 346    
Investments, at fair value, ending balance 330 [2],[10],[25],[31],[32]     330 [2],[10],[25],[31],[32]   346 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Camelia Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[31],[32]     0 [2],[10],[13],[25],[31],[32]   0 [1],[5],[8],[12],[29],[30]
Investment, Identifier [Axis]: Captive Resources Midco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     15,470 15,470    
Investments, at fair value, ending balance 23,157 [2],[10]     23,157 [2],[10]   15,470 [1],[5],[9],[14]
Investment, Identifier [Axis]: Captive Resources Midco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Cavender Stores L.P. Senior Secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16]     5,459 5,459    
Investments, at fair value, ending balance [1],[16]           5,459
Investment, Identifier [Axis]: Cavender Stores L.P., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11] 5,418     5,418    
Investment, Identifier [Axis]: Celerion Buyer, Inc., LP units 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,302 1,302    
Investments, at fair value, ending balance 891 [2],[10],[27]     891 [2],[10],[27]   1,302 [1],[5]
Investment, Identifier [Axis]: Celerion Buyer, Inc., LP units 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     982 982    
Investments, at fair value, ending balance 3,108 [2],[10]     3,108 [2],[10]   982 [1],[5]
Investment, Identifier [Axis]: Celerion Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[16],[18]     29,605 29,605    
Investments, at fair value, ending balance 30,943 [2],[10],[11]     30,943 [2],[10],[11]   29,605 [1],[6],[16],[18]
Investment, Identifier [Axis]: Celerion Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Celerion Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Celerion Buyer, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11] 21,957     21,957    
Investment, Identifier [Axis]: Ceres Groupe SAS & Ceres PikCo, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[35]     16,430 16,430    
Investments, at fair value, ending balance 17,547 [2],[10],[25],[32],[36]     17,547 [2],[10],[25],[32],[36]   16,430 [1],[5],[8],[30],[35]
Investment, Identifier [Axis]: Ceres Groupe SAS & Ceres PikCo, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[35]     0 0    
Investments, at fair value, ending balance 2,486 [2],[10],[25],[32],[36]     2,486 [2],[10],[25],[32],[36]   0 [1],[5],[8],[30],[35]
Investment, Identifier [Axis]: Ceres Groupe SAS & Ceres PikCo, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[35]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[32],[36]     0 [2],[10],[25],[32],[36]   0 [1],[5],[8],[30],[35]
Investment, Identifier [Axis]: Ceres Groupe SAS & Ceres PikCo, Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[35]     1,916 1,916    
Investments, at fair value, ending balance 2,171 [2],[10],[15],[25],[32],[36]     2,171 [2],[10],[15],[25],[32],[36]   1,916 [1],[5],[8],[14],[30],[35]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     1,730 1,730    
Investments, at fair value, ending balance 1,730 [2],[11]     1,730 [2],[11]   1,730 [1],[16],[18]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     142 142    
Investments, at fair value, ending balance 260 [2],[10]     260 [2],[10]   142 [1],[5]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     60 60    
Investments, at fair value, ending balance 142 [2],[10]     142 [2],[10]   60 [1],[5]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 60 [2],[10]     60 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,336     2,336    
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,456     1,456    
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     1,659 1,659    
Investments, at fair value, ending balance 1,659 [2],[11]     1,659 [2],[11]   1,659 [1],[16],[18]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,197 1,197    
Investments, at fair value, ending balance 1,197 [2],[10],[11]     1,197 [2],[10],[11]   1,197 [1],[5]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     1,182 1,182    
Investments, at fair value, ending balance 1,182 [2],[11]     1,182 [2],[11]   1,182 [1],[16],[18]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     820 820    
Investments, at fair value, ending balance 820 [2],[10],[11]     820 [2],[10],[11]   820 [1],[5],[16]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     723 723    
Investments, at fair value, ending balance 723 [2],[11]     723 [2],[11]   723 [1],[16],[18]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     704 704    
Investments, at fair value, ending balance 704 [2],[10]     704 [2],[10]   704 [1],[5]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     416 416    
Investments, at fair value, ending balance 416 [2],[10],[11]     416 [2],[10],[11]   416 [1],[5],[16]
Investment, Identifier [Axis]: Certus Pest, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     260 260    
Investments, at fair value, ending balance 394 [2],[10]     394 [2],[10]   260 [1],[5]
Investment, Identifier [Axis]: Chase Industries, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[37]     13,145 13,145    
Investments, at fair value, ending balance 13,318 [2],[10],[15],[38]     13,318 [2],[10],[15],[38]   13,145 [1],[5],[14],[37]
Investment, Identifier [Axis]: Chase Industries, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[37]     1,242 1,242    
Investments, at fair value, ending balance 1,259 [2],[10],[15],[38]     1,259 [2],[10],[15],[38]   1,242 [1],[5],[14],[37]
Investment, Identifier [Axis]: Chase Industries, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[37]     228 228    
Investments, at fair value, ending balance 252 [2],[10],[15],[38]     252 [2],[10],[15],[38]   228 [1],[5],[14],[37]
Investment, Identifier [Axis]: Chase Intermediate, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     337 337    
Investments, at fair value, ending balance 401 [2],[10]     401 [2],[10]   337 [1],[5]
Investment, Identifier [Axis]: Chase Intermediate, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17],[18]     49,331 49,331    
Investments, at fair value, ending balance 48,952 [2],[10],[11]     48,952 [2],[10],[11]   49,331 [1],[5],[9],[16],[17],[18]
Investment, Identifier [Axis]: Chase Intermediate, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 80 [2],[10]     80 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Chase Intermediate, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     938 938    
Investments, at fair value, ending balance 2,289 [2],[10]     2,289 [2],[10]   938 [1],[5]
Investment, Identifier [Axis]: Chase Intermediate, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 599     599    
Investment, Identifier [Axis]: Chestnut Optical Midco, Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     93,864 93,864    
Gross additions       3,490    
Gross reductions       0    
Net change in unrealized appreciation (depreciation)       3,814    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 101,168     101,168   93,864
Interest, dividend and fee income       2,557    
Investment, Identifier [Axis]: Chestnut Optical Midco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 39,657     39,657    
Investment, Identifier [Axis]: Chestnut Optical Midco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (338)     (338)    
Investment, Identifier [Axis]: Chestnut Optical Midco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,014     1,014    
Investment, Identifier [Axis]: Citrin Cooperman Advisors LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     8,058 8,058    
Investments, at fair value, ending balance [1],[5]           8,058
Investment, Identifier [Axis]: Citrin Cooperman Advisors LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     3,498 3,498    
Investments, at fair value, ending balance [1],[5],[17]           3,498
Investment, Identifier [Axis]: Citrin Cooperman Advisors LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,038 1,038    
Investments, at fair value, ending balance [1],[5]           1,038
Investment, Identifier [Axis]: Citrin Cooperman Advisors LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     664 664    
Investments, at fair value, ending balance [1],[5]           664
Investment, Identifier [Axis]: Citrin Cooperman Advisors LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     253 253    
Investments, at fair value, ending balance [1],[5],[9]           253
Investment, Identifier [Axis]: CivicPlus, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     9,175 9,175    
Investments, at fair value, ending balance [1],[5],[14],[19]           9,175
Investment, Identifier [Axis]: CivicPlus, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     5,430 5,430    
Investments, at fair value, ending balance 23,440 [2],[10],[20]     23,440 [2],[10],[20]   5,430 [1],[5],[9],[14]
Investment, Identifier [Axis]: CivicPlus, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     4,301 4,301    
Investments, at fair value, ending balance (19) [2],[10],[13]     (19) [2],[10],[13]   4,301 [1],[5],[9],[14]
Investment, Identifier [Axis]: CivicPlus, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     552 552    
Investments, at fair value, ending balance 366 [2],[10],[15]     366 [2],[10],[15]   552 [1],[5],[14]
Investment, Identifier [Axis]: CivicPlus, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance (1) [2],[10],[13]     (1) [2],[10],[13]   0 [1],[5]
Investment, Identifier [Axis]: Cloudbees ., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     797 797    
Investments, at fair value, ending balance [1],[5]           797
Investment, Identifier [Axis]: Cloudbees, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,021 2,021    
Investments, at fair value, ending balance 2,113 [2],[10]     2,113 [2],[10]   2,021 [1],[5]
Investment, Identifier [Axis]: Cloudbees, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 807     807    
Investment, Identifier [Axis]: Cloudbees, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,157 1,157    
Investments, at fair value, ending balance 1,103 [2],[10]     1,103 [2],[10]   1,157 [1],[5]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     27 27    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   27 [1],[5]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     14,651 14,651    
Investments, at fair value, ending balance 14,722 [2],[10],[11]     14,722 [2],[10],[11]   14,651 [1],[5],[17]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,913 4,913    
Investments, at fair value, ending balance 4,937 [2],[10]     4,937 [2],[10]   4,913 [1],[5]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,711 3,711    
Investments, at fair value, ending balance 3,730 [2],[10]     3,730 [2],[10]   3,711 [1],[5],[9]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     128 128    
Investments, at fair value, ending balance 439 [2],[10]     439 [2],[10]   128 [1],[5]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6,317 6,317    
Investments, at fair value, ending balance 6,349 [2],[10]     6,349 [2],[10]   6,317 [1],[5]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (80) (80)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (80) [1],[5],[12]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     17,048 17,048    
Investments, at fair value, ending balance 18,783 [2],[10],[27]     18,783 [2],[10],[27]   17,048 [1],[5],[26]
Investment, Identifier [Axis]: Cobalt Buyer Sub, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     306 306    
Investments, at fair value, ending balance 134 [2],[10]     134 [2],[10]   306 [1],[5]
Investment, Identifier [Axis]: Cobepa BlueSky Aggregator, SCSp, LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     670 670    
Investments, at fair value, ending balance [1],[5]           670
Investment, Identifier [Axis]: Cobepa BlueSky Aggregator, SCSp, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 67     67    
Investment, Identifier [Axis]: Cobepa BlueSky Aggregator, SCSp, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     41 41    
Investments, at fair value, ending balance 43 [2],[10],[27]     43 [2],[10],[27]   41 [1],[5]
Investment, Identifier [Axis]: Cobepa BlueSky Aggregator, SCSp, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     53 53    
Investments, at fair value, ending balance 57 [2],[10],[27]     57 [2],[10],[27]   53 [1],[5],[26]
Investment, Identifier [Axis]: Collision SP Subco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     886 886    
Investments, at fair value, ending balance 2,205 [2],[10]     2,205 [2],[10]   886 [1],[5],[9]
Investment, Identifier [Axis]: Collision SP Subco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     162 162    
Investments, at fair value, ending balance 1,133 [2],[10]     1,133 [2],[10]   162 [1],[5]
Investment, Identifier [Axis]: Collision SP Subco, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     14 14    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   14 [1],[5]
Investment, Identifier [Axis]: Collision SP Subco, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 245     245    
Investment, Identifier [Axis]: Collision SP Subco, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Color Intermediate, LLC, Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     17,565 17,565    
Investments, at fair value, ending balance 17,259 [2],[10],[11]     17,259 [2],[10],[11]   17,565 [1],[5],[9]
Investment, Identifier [Axis]: Community Care Partners, LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,385 3,385    
Investments, at fair value, ending balance 3,463 [2],[10]     3,463 [2],[10]   3,385 [1],[5],[9]
Investment, Identifier [Axis]: Connexin Software, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     301 301    
Investments, at fair value, ending balance 325 [2],[10]     325 [2],[10]   301 [1],[5]
Investment, Identifier [Axis]: Connexin Software, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     23 23    
Investments, at fair value, ending balance 26 [2],[10]     26 [2],[10]   23 [1],[5]
Investment, Identifier [Axis]: Connexin Software, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     11,759 11,759    
Investments, at fair value, ending balance 11,759 [2],[10]     11,759 [2],[10]   11,759 [1],[5],[9]
Investment, Identifier [Axis]: Connexin Software, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     38,182 38,182    
Investments, at fair value, ending balance [1],[5],[8],[9],[29],[30]           38,182
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     130 130    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           130
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     127 127    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           127
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     95 95    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           95
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     114 114    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           114
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     60 60    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           60
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     140 140    
Investments, at fair value, ending balance [1],[5],[8],[29]           140
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     0 0    
Investments, at fair value, ending balance [1],[5],[8],[29]           0
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 17            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     58 58    
Investments, at fair value, ending balance [1],[5],[8],[29]           58
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     15,686 15,686    
Investments, at fair value, ending balance [1],[5],[8],[9],[29]           15,686
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[8],[17],[18],[29]     15,587 15,587    
Investments, at fair value, ending balance [1],[8],[17],[18],[29]           15,587
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[8],[16],[18],[29]     2,935 2,935    
Investments, at fair value, ending balance [1],[8],[16],[18],[29]           2,935
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[8],[16],[18],[29]     1,951 1,951    
Investments, at fair value, ending balance [1],[8],[16],[18],[29]           1,951
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[16],[29]     998 998    
Investments, at fair value, ending balance [1],[5],[8],[16],[29]           998
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     500 500    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           500
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     222 222    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           222
Investment, Identifier [Axis]: Consilio Midco Limited, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     168 168    
Investments, at fair value, ending balance [1],[5],[8],[29]           168
Investment, Identifier [Axis]: Consilio Midco Limited, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 13,114     13,114    
Investment, Identifier [Axis]: Consilio Midco Limited, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 10,636     10,636    
Investment, Identifier [Axis]: Consilio Midco Limited, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 6,555     6,555    
Investment, Identifier [Axis]: Consilio Midco Limited, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] (19)     (19)    
Investment, Identifier [Axis]: Consilio Midco Limited, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] (12)     (12)    
Investment, Identifier [Axis]: Consilio Midco Limited, Subordinated debt 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 1,340     1,340    
Investment, Identifier [Axis]: Consilio Midco Limited, Subordinated debt 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 1,669     1,669    
Investment, Identifier [Axis]: Consilio Midco Limited, Subordinated debt 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] (6)     (6)    
Investment, Identifier [Axis]: Consor Intermediate II, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     4,050 4,050    
Investments, at fair value, ending balance 4,742 [2],[10],[11]     4,742 [2],[10],[11]   4,050 [1],[5],[16]
Investment, Identifier [Axis]: Consor Intermediate II, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Consor Intermediate II, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 534 [2],[10]     534 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Corsair Blade IV S.A R.L., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[39] 3,674     3,674    
Investment, Identifier [Axis]: Corsair Blade IV S.A R.L., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[32],[39] 1,208     1,208    
Investment, Identifier [Axis]: Coupa Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     31,960 31,960    
Investments, at fair value, ending balance 31,719 [2],[10]     31,719 [2],[10]   31,960 [1],[5],[9]
Investment, Identifier [Axis]: Coupa Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Coupa Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Covercraft Parent III, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     6,621 6,621    
Investments, at fair value, ending balance 5,893 [2],[10]     5,893 [2],[10]   6,621 [1],[5],[17]
Investment, Identifier [Axis]: Covercraft Parent III, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,339 1,339    
Investments, at fair value, ending balance 1,193 [2],[10]     1,193 [2],[10]   1,339 [1],[5]
Investment, Identifier [Axis]: Covercraft Parent III, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     54 54    
Investments, at fair value, ending balance 162 [2],[10]     162 [2],[10]   54 [1],[5]
Investment, Identifier [Axis]: Creek Parent, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,651     3,651    
Investment, Identifier [Axis]: Creek Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 56,687     56,687    
Investment, Identifier [Axis]: Creek Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Crewline Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,403 5,403    
Investments, at fair value, ending balance 10,857 [2],[10]     10,857 [2],[10]   5,403 [1],[5],[9]
Investment, Identifier [Axis]: Crewline Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Critical Start, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     175 175    
Investments, at fair value, ending balance 156 [2],[10]     156 [2],[10]   175 [1],[5]
Investment, Identifier [Axis]: Critical Start, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     5,201 5,201    
Investments, at fair value, ending balance 5,347 [2],[10],[15]     5,347 [2],[10],[15]   5,201 [1],[5],[9],[14]
Investment, Identifier [Axis]: Critical Start, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     2,388 2,388    
Investments, at fair value, ending balance 2,455 [2],[10],[15]     2,455 [2],[10],[15]   2,388 [1],[5],[9],[14]
Investment, Identifier [Axis]: Critical Start, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance 66 [2],[10]     66 [2],[10]   (2) [1],[5],[12]
Investment, Identifier [Axis]: Crow River Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     6,032 6,032    
Investments, at fair value, ending balance 6,032 [2],[10]     6,032 [2],[10]   6,032 [1],[5],[9]
Investment, Identifier [Axis]: Crow River Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     26 26    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   26 [1],[5]
Investment, Identifier [Axis]: Crow River Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 8,700     8,700    
Investment, Identifier [Axis]: Crumbl Enterprises, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 32,245     32,245    
Investment, Identifier [Axis]: Crumbl Enterprises, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 408     408    
Investment, Identifier [Axis]: Crunch Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     56,836 56,836    
Investments, at fair value, ending balance 1,760 [2],[10]     1,760 [2],[10]   56,836 [1],[5]
Investment, Identifier [Axis]: Crunch Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (39) (39)    
Investments, at fair value, ending balance (1) [2],[10],[13]     (1) [2],[10],[13]   (39) [1],[5],[12]
Investment, Identifier [Axis]: Cycle Gear, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     183 183    
Investments, at fair value, ending balance 258 [2],[10]     258 [2],[10]   183 [1],[5]
Investment, Identifier [Axis]: Cycle Gear, Inc., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[18]     45,133 45,133    
Investments, at fair value, ending balance 46,304 [2],[10]     46,304 [2],[10]   45,133 [1],[5],[6],[18]
Investment, Identifier [Axis]: Cycle Gear, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     150 150    
Investments, at fair value, ending balance 156 [2],[10]     156 [2],[10]   150 [1],[5]
Investment, Identifier [Axis]: Cynet Security Ltd., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[40]     1,008 1,008    
Investments, at fair value, ending balance 1,074 [2],[10],[25],[41]     1,074 [2],[10],[25],[41]   1,008 [1],[5],[8],[40]
Investment, Identifier [Axis]: DCA Investment Holding, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     0 0    
Investments, at fair value, ending balance 0 [2]     0 [2]   0 [1]
Investment, Identifier [Axis]: DCA Investment Holding, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[26]     783 783    
Investments, at fair value, ending balance 100 [2],[22],[27]     100 [2],[22],[27]   783 [1],[26]
Investment, Identifier [Axis]: DCCM, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 591     591    
Investment, Identifier [Axis]: DCCM, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: DCCM, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: DISA Holdings Corp., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     691 691    
Investments, at fair value, ending balance 686 [2],[10]     686 [2],[10]   691 [1],[5]
Investment, Identifier [Axis]: DISA Holdings Corp., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,242 5,242    
Investments, at fair value, ending balance 5,201 [2],[10]     5,201 [2],[10]   5,242 [1],[5],[9]
Investment, Identifier [Axis]: DISA Holdings Corp., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     808 808    
Investments, at fair value, ending balance 802 [2],[10]     802 [2],[10]   808 [1],[5],[9]
Investment, Identifier [Axis]: DISA Holdings Corp., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     611 611    
Investments, at fair value, ending balance 607 [2],[10]     607 [2],[10]   611 [1],[5]
Investment, Identifier [Axis]: DISA Holdings Corp., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     70 70    
Investments, at fair value, ending balance 589 [2],[10]     589 [2],[10]   70 [1],[5]
Investment, Identifier [Axis]: DISA Holdings Corp., Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 34 [2],[10]     34 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: DISA Holdings Corp., Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     104 104    
Investments, at fair value, ending balance 104 [2],[10],[15]     104 [2],[10],[15]   104 [1],[5],[14]
Investment, Identifier [Axis]: DP Flores Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     137 137    
Investments, at fair value, ending balance 169 [2],[10]     169 [2],[10]   137 [1],[5]
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     764 764    
Investments, at fair value, ending balance 771 [2],[10],[25],[31]     771 [2],[10],[25],[31]   764 [1],[5],[8],[29]
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     473 473    
Investments, at fair value, ending balance 491 [2],[10],[25],[31],[32]     491 [2],[10],[25],[31],[32]   473 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29]     (2) (2)    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[31]     0 [2],[10],[13],[25],[31]   (2) [1],[5],[8],[12],[29]
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29]     (1) (1)    
Investments, at fair value, ending balance 18 [2],[10],[25],[31]     18 [2],[10],[25],[31]   (1) [1],[5],[8],[12],[29]
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 4     4    
Investment, Identifier [Axis]: Datix Bidco Limited and RL Datix Holdings, Inc., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     0 0    
Investments, at fair value, ending balance [1],[5],[8],[29]           0
Investment, Identifier [Axis]: Davidson Hotel Company, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     6,716 6,716    
Investments, at fair value, ending balance [1],[5],[17]           6,716
Investment, Identifier [Axis]: Davidson Hotel Company, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,160 1,160    
Investments, at fair value, ending balance [1],[5]           1,160
Investment, Identifier [Axis]: Davidson Hotel Company, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Daxko Acquisition Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[19]     39,458 39,458    
Investments, at fair value, ending balance 39,153 [2],[11],[20]     39,153 [2],[11],[20]   39,458 [1],[5],[16],[19]
Investment, Identifier [Axis]: Daxko Acquisition Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     3,328 3,328    
Investments, at fair value, ending balance 3,302 [2],[10],[11]     3,302 [2],[10],[11]   3,328 [1],[5],[17]
Investment, Identifier [Axis]: Daxko Acquisition Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     199 199    
Investments, at fair value, ending balance 198 [2],[10]     198 [2],[10]   199 [1],[5]
Investment, Identifier [Axis]: Daxko Acquisition Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     64 64    
Investments, at fair value, ending balance 133 [2],[10]     133 [2],[10]   64 [1],[5]
Investment, Identifier [Axis]: Daxko Acquisition Corporation, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Delinea Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     22,609 22,609    
Investments, at fair value, ending balance 22,434 [2],[11],[20]     22,434 [2],[11],[20]   22,609 [1],[5],[19]
Investment, Identifier [Axis]: Delinea Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[18],[19]     13,127 13,127    
Investments, at fair value, ending balance 13,025 [2],[11],[20]     13,025 [2],[11],[20]   13,127 [1],[18],[19]
Investment, Identifier [Axis]: Delinea Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 11,414 [2],[10]     11,414 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Delinea Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9]     11,500 11,500    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   11,500 [1],[9]
Investment, Identifier [Axis]: Denali Bidco Limited, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     824 824    
Investments, at fair value, ending balance 1,033 [2],[10],[25],[31]     1,033 [2],[10],[25],[31]   824 [1],[5],[8],[29]
Investment, Identifier [Axis]: Denali Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     7,903 7,903    
Investments, at fair value, ending balance 8,073 [2],[10],[25],[31],[32]     8,073 [2],[10],[25],[31],[32]   7,903 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Denali Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     2,669 2,669    
Investments, at fair value, ending balance 2,811 [2],[10],[25],[31],[32]     2,811 [2],[10],[25],[31],[32]   2,669 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Denali Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     1,906 1,906    
Investments, at fair value, ending balance 2,007 [2],[10],[25],[31],[32]     2,007 [2],[10],[25],[31],[32]   1,906 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Denali Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     741 741    
Investments, at fair value, ending balance 784 [2],[10],[25],[31],[32]     784 [2],[10],[25],[31],[32]   741 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Denali Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[31],[32]     0 [2],[10],[13],[25],[31],[32]   0 [1],[5],[8],[12],[29],[30]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     44,627 44,627    
Investments, at fair value, ending balance 38,258 [2],[11]     38,258 [2],[11]   44,627 [1],[5],[16]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,254 1,254    
Investments, at fair value, ending balance 1,075 [2],[10]     1,075 [2],[10]   1,254 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,034 1,034    
Investments, at fair value, ending balance 887 [2],[10]     887 [2],[10]   1,034 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     469 469    
Investments, at fair value, ending balance 1,212 [2],[10]     1,212 [2],[10]   469 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     406 406    
Investments, at fair value, ending balance 403 [2],[10]     403 [2],[10]   406 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     394 394    
Investments, at fair value, ending balance 348 [2],[10]     348 [2],[10]   394 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     343 343    
Investments, at fair value, ending balance 294 [2],[10]     294 [2],[10]   343 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     201 201    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   201 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 17            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     200 200    
Investments, at fair value, ending balance 173 [2],[10]     173 [2],[10]   200 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 18            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     101 101    
Investments, at fair value, ending balance 87 [2],[10]     87 [2],[10]   101 [1],[5]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 19            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     10,401 10,401    
Investments, at fair value, ending balance 8,917 [2],[10]     8,917 [2],[10]   10,401 [1],[5],[9],[17]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     3,113 3,113    
Investments, at fair value, ending balance 2,668 [2],[10]     2,668 [2],[10]   3,113 [1],[5],[17]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,891 1,891    
Investments, at fair value, ending balance 1,621 [2],[10]     1,621 [2],[10]   1,891 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,797 1,797    
Investments, at fair value, ending balance 1,540 [2],[10]     1,540 [2],[10]   1,797 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,568 1,568    
Investments, at fair value, ending balance 1,344 [2],[10]     1,344 [2],[10]   1,568 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,508 1,508    
Investments, at fair value, ending balance 1,293 [2],[10]     1,293 [2],[10]   1,508 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,292 1,292    
Investments, at fair value, ending balance 1,108 [2],[10]     1,108 [2],[10]   1,292 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,254 1,254    
Investments, at fair value, ending balance 1,075 [2],[10]     1,075 [2],[10]   1,254 [1],[5],[9]
Investment, Identifier [Axis]: Denali Midco 2, LLC, Second lien            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 11,207     11,207    
Investment, Identifier [Axis]: Diligent Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,985 8,985    
Investments, at fair value, ending balance 8,985 [2],[10]     8,985 [2],[10]   8,985 [1],[5],[9]
Investment, Identifier [Axis]: Diligent Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,541 1,541    
Investments, at fair value, ending balance 1,541 [2],[10]     1,541 [2],[10]   1,541 [1],[5]
Investment, Identifier [Axis]: Diligent Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Diligent Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 70 [2],[10]     70 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Diligent Corporation, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     31,231 31,231    
Investments, at fair value, ending balance [1],[5],[26]           31,231
Investment, Identifier [Axis]: Diligent Corporation, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,543 2,543    
Investments, at fair value, ending balance [1],[5]           2,543
Investment, Identifier [Axis]: Diligent Corporation, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 34,382     34,382    
Investment, Identifier [Axis]: Diligent Corporation, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,762     1,762    
Investment, Identifier [Axis]: Disco Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     6,246 6,246    
Investments, at fair value, ending balance 9,240 [2],[10]     9,240 [2],[10]   6,246 [1],[5],[9]
Investment, Identifier [Axis]: Disco Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Dollfus Mieg Company, Inc, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     925 925    
Investments, at fair value, ending balance [1],[5],[8],[9],[29]           925
Investment, Identifier [Axis]: Dollfus Mieg Company, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     2,112 2,112    
Investments, at fair value, ending balance 2,112 [2],[10],[25],[31]     2,112 [2],[10],[25],[31]   2,112 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Dollfus Mieg Company, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     1,052 1,052    
Investments, at fair value, ending balance 1,052 [2],[10],[25],[31]     1,052 [2],[10],[25],[31]   1,052 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Dollfus Mieg Company, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 925     925    
Investment, Identifier [Axis]: Doxa Insurance Holdings LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,739 1,739    
Investments, at fair value, ending balance 1,722 [2],[10]     1,722 [2],[10]   1,739 [1],[5],[9]
Investment, Identifier [Axis]: Doxa Insurance Holdings LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 1,622 [2],[10]     1,622 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Doxa Insurance Holdings LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,438 1,438    
Investments, at fair value, ending balance 12 [2],[10]     12 [2],[10]   1,438 [1],[5]
Investment, Identifier [Axis]: Doxa Insurance Holdings LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Dragon UK Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     22,807 22,807    
Investments, at fair value, ending balance [1],[5],[8],[9],[29],[30]           22,807
Investment, Identifier [Axis]: Dragon UK Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     4,447 4,447    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           4,447
Investment, Identifier [Axis]: Dragon UK Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     (19) (19)    
Investments, at fair value, ending balance [1],[5],[8],[12],[29],[30]           (19)
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,827 5,827    
Investments, at fair value, ending balance 53,333 [2],[10],[25],[32]     53,333 [2],[10],[25],[32]   5,827 [1],[5],[9]
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,489 [2],[10]     1,489 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,477 1,477    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[32]     0 [2],[10],[13],[25],[32]   1,477 [1],[5]
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     472 472    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   472 [1],[5],[9]
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 5,782 [2],[10]     5,782 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 415     415    
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,466     1,466    
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 469     469    
Investment, Identifier [Axis]: Dwyer Instruments, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 549     549    
Investment, Identifier [Axis]: EMS LINQ, LLC, LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     748 748    
Investments, at fair value, ending balance [1],[5]           748
Investment, Identifier [Axis]: EMS LINQ, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 394     394    
Investment, Identifier [Axis]: EMS LINQ, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     13,835 13,835    
Investments, at fair value, ending balance 13,835 [2],[10],[20]     13,835 [2],[10],[20]   13,835 [1],[5],[19]
Investment, Identifier [Axis]: EMS LINQ, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     96 96    
Investments, at fair value, ending balance 146 [2],[10]     146 [2],[10]   96 [1],[5]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[18]     10,981 10,981    
Investments, at fair value, ending balance 10,985 [2],[10],[11]     10,985 [2],[10],[11]   10,981 [1],[5],[16],[18]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (1) (1)    
Investments, at fair value, ending balance 1,698 [2],[10]     1,698 [2],[10]   (1) [1],[5],[12]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (106) (106)    
Investments, at fair value, ending balance 601 [2],[10]     601 [2],[10]   (106) [1],[5],[12]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,809 2,809    
Investments, at fair value, ending balance 7,463 [2],[10]     7,463 [2],[10]   2,809 [1],[5]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,788 1,788    
Investments, at fair value, ending balance 2,809 [2],[10]     2,809 [2],[10]   1,788 [1],[5]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,761 1,761    
Investments, at fair value, ending balance 1,788 [2],[10]     1,788 [2],[10]   1,761 [1],[5],[9]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,475 1,475    
Investments, at fair value, ending balance 1,761 [2],[10]     1,761 [2],[10]   1,475 [1],[5],[9]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,226 1,226    
Investments, at fair value, ending balance 1,475 [2],[10]     1,475 [2],[10]   1,226 [1],[5],[9]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,084 1,084    
Investments, at fair value, ending balance 1,226 [2],[10]     1,226 [2],[10]   1,084 [1],[5]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,061 1,061    
Investments, at fair value, ending balance 1,084 [2],[10]     1,084 [2],[10]   1,061 [1],[5]
Investment, Identifier [Axis]: EOS Fitness Opco Holdings, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     446 446    
Investments, at fair value, ending balance 1,061 [2],[10]     1,061 [2],[10]   446 [1],[5]
Investment, Identifier [Axis]: ERC Topco Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 4,650     4,650    
Investment, Identifier [Axis]: ERC Topco Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[17],[21]     16,178 16,178    
Investments, at fair value, ending balance 6,810 [2],[10],[15]     6,810 [2],[10],[15]   16,178 [1],[5],[9],[14],[17],[21]
Investment, Identifier [Axis]: ERC Topco Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     112 112    
Investments, at fair value, ending balance 1,069 [2],[10]     1,069 [2],[10]   112 [1],[5],[14],[21]
Investment, Identifier [Axis]: ERC Topco Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[17],[21]     275 275    
Investments, at fair value, ending balance 76 [2],[10],[15]     76 [2],[10],[15]   275 [1],[5],[9],[14],[17],[21]
Investment, Identifier [Axis]: ERC Topco Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     2 2    
Investments, at fair value, ending balance [1],[5],[14],[21]           2
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[16],[17]     5,409 5,409    
Investments, at fair value, ending balance 5,367 [2],[10],[11]     5,367 [2],[10],[11]   5,409 [1],[6],[16],[17]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     924 924    
Investments, at fair value, ending balance 1,589 [2],[10]     1,589 [2],[10]   924 [1],[5]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     817 817    
Investments, at fair value, ending balance 917 [2],[10]     917 [2],[10]   817 [1],[5]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     375 375    
Investments, at fair value, ending balance 811 [2],[10]     811 [2],[10]   375 [1],[5]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     265 265    
Investments, at fair value, ending balance 439 [2],[10]     439 [2],[10]   265 [1],[5]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     209 209    
Investments, at fair value, ending balance 546 [2],[10]     546 [2],[10]   209 [1],[5]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 372 [2],[10]     372 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 209     209    
Investment, Identifier [Axis]: ESN Venture Holdings, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 181     181    
Investment, Identifier [Axis]: ESO Solution, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     11,360 11,360    
Investments, at fair value, ending balance 11,360 [2],[10],[20]     11,360 [2],[10],[20]   11,360 [1],[5],[9],[19]
Investment, Identifier [Axis]: ESO Solution, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,803 3,803    
Investments, at fair value, ending balance 3,803 [2],[10]     3,803 [2],[10]   3,803 [1],[5]
Investment, Identifier [Axis]: ESO Solution, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     78 78    
Investments, at fair value, ending balance 142 [2],[10]     142 [2],[10]   78 [1],[5]
Investment, Identifier [Axis]: EWC Growth Partners LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: EWC Growth Partners LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     939 939    
Investments, at fair value, ending balance 1,034 [2],[10]     1,034 [2],[10]   939 [1],[5],[9]
Investment, Identifier [Axis]: EWC Growth Partners LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     1,103 1,103    
Investments, at fair value, ending balance 881 [2],[10]     881 [2],[10]   1,103 [1],[5],[17]
Investment, Identifier [Axis]: EWC Growth Partners LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     36 36    
Investments, at fair value, ending balance 98 [2],[10]     98 [2],[10]   36 [1],[5]
Investment, Identifier [Axis]: EWC Growth Partners LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     105 105    
Investments, at fair value, ending balance 36 [2],[10]     36 [2],[10]   105 [1],[5]
Investment, Identifier [Axis]: Eagle Family Foods Group, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     13,298 13,298    
Investments, at fair value, ending balance 12,912 [2],[10]     12,912 [2],[10]   13,298 [1],[5]
Investment, Identifier [Axis]: Eagle Family Foods Group, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     186 186    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   186 [1],[5]
Investment, Identifier [Axis]: Eclipse Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     14,140 14,140    
Investments, at fair value, ending balance 14,283 [2],[10]     14,283 [2],[10]   14,140 [1],[5]
Investment, Identifier [Axis]: Eclipse Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (18) (18)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (18) [1],[5],[12]
Investment, Identifier [Axis]: Eclipse Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (12) (12)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (12) [1],[5],[12]
Investment, Identifier [Axis]: Eclipse Buyer, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,595 1,595    
Investments, at fair value, ending balance 1,797 [2],[10],[27]     1,797 [2],[10],[27]   1,595 [1],[5],[26]
Investment, Identifier [Axis]: Einstein Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 8,972     8,972    
Investment, Identifier [Axis]: Einstein Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (9)     (9)    
Investment, Identifier [Axis]: Eliassen Group, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,084 2,084    
Investments, at fair value, ending balance 2,090 [2],[10]     2,090 [2],[10]   2,084 [1],[5],[9]
Investment, Identifier [Axis]: Eliassen Group, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     140 140    
Investments, at fair value, ending balance 141 [2],[10]     141 [2],[10]   140 [1],[5]
Investment, Identifier [Axis]: Elite Dental Partners LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     11,696 11,696 13,396 13,396
Gross additions       3,244   5,845
Gross reductions       (2,540)   (3,013)
Net change in unrealized appreciation (depreciation)       (941)   (4,532)
Net realized gain (loss)       0   0
Investments, at fair value, ending balance 11,459     11,459   11,696
Interest, dividend and fee income       156   180
Investment, Identifier [Axis]: Elite Dental Partners LLC, LLC interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     0 0    
Investments, at fair value, ending balance 0 [2]     0 [2]   0 [1]
Investment, Identifier [Axis]: Elite Dental Partners LLC, LLC interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     0 0    
Investments, at fair value, ending balance 0 [2]     0 [2]   0 [1]
Investment, Identifier [Axis]: Elite Dental Partners LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     0 0    
Investments, at fair value, ending balance 0 [2]     0 [2]   0 [1]
Investment, Identifier [Axis]: Elite Dental Partners LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     5,505 5,505    
Investments, at fair value, ending balance 5,205 [2],[10],[15],[22]     5,205 [2],[10],[15],[22]   5,505 [1],[5],[14],[21]
Investment, Identifier [Axis]: Elite Dental Partners LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     4,393 4,393    
Investments, at fair value, ending balance 3,752 [2],[10],[15],[22]     3,752 [2],[10],[15],[22]   4,393 [1],[5],[14],[21]
Investment, Identifier [Axis]: Elite Dental Partners LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,798 1,798    
Investments, at fair value, ending balance 1,935 [2],[10],[15]     1,935 [2],[10],[15]   1,798 [1],[5],[14]
Investment, Identifier [Axis]: Elite Dental Partners LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 567     567    
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     9,951 9,951    
Investments, at fair value, ending balance 9,943 [2],[10],[15]     9,943 [2],[10],[15]   9,951 [1],[5],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,999 3,999    
Investments, at fair value, ending balance 3,996 [2],[10],[15]     3,996 [2],[10],[15]   3,999 [1],[5],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     2,058 2,058    
Investments, at fair value, ending balance 2,057 [2],[10],[15]     2,057 [2],[10],[15]   2,058 [1],[5],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[14]     683 683    
Investments, at fair value, ending balance 683 [2],[10],[15]     683 [2],[10],[15]   683 [1],[5],[6],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     312 312    
Investments, at fair value, ending balance 312 [2],[10],[15]     312 [2],[10],[15]   312 [1],[5],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[14]     298 298    
Investments, at fair value, ending balance 299 [2],[10],[15]     299 [2],[10],[15]   298 [1],[5],[6],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     115 115    
Investments, at fair value, ending balance 1,086 [2],[10],[15]     1,086 [2],[10],[15]   115 [1],[5],[14]
Investment, Identifier [Axis]: Elite Sportswear, L.P., Senior secured 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     4 4    
Investments, at fair value, ending balance 37 [2],[10],[15]     37 [2],[10],[15]   4 [1],[5],[14]
Investment, Identifier [Axis]: Emerge Intermediate, Inc., LLC units 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     435 435    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   435 [1],[5]
Investment, Identifier [Axis]: Emerge Intermediate, Inc., LLC units 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     108 108    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   108 [1],[5]
Investment, Identifier [Axis]: Emerge Intermediate, Inc., LLC units 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Empyrean Solutions, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 9,283     9,283    
Investment, Identifier [Axis]: Empyrean Solutions, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Empyrean Solutions, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Enboarder, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[42]     567 567    
Investments, at fair value, ending balance 550 [2],[10],[25]     550 [2],[10],[25]   567 [1],[5],[8],[42]
Investment, Identifier [Axis]: Encore Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,575 4,575    
Investments, at fair value, ending balance [1],[5]           4,575
Investment, Identifier [Axis]: Encore Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     910 910    
Investments, at fair value, ending balance [1],[5],[9]           910
Investment, Identifier [Axis]: Encore Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,170 1,170    
Investments, at fair value, ending balance [1],[5]           1,170
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     15,047 15,047    
Investments, at fair value, ending balance 15,436 [2],[10]     15,436 [2],[10]   15,047 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     804 804    
Investments, at fair value, ending balance 825 [2],[10]     825 [2],[10]   804 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     408 408    
Investments, at fair value, ending balance 419 [2],[10]     419 [2],[10]   408 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     345 345    
Investments, at fair value, ending balance 354 [2],[10]     354 [2],[10]   345 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     169 169    
Investments, at fair value, ending balance 173 [2],[10]     173 [2],[10]   169 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     162 162    
Investments, at fair value, ending balance 167 [2],[10]     167 [2],[10]   162 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     90 90    
Investments, at fair value, ending balance 157 [2],[10]     157 [2],[10]   90 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     89 89    
Investments, at fair value, ending balance 101 [2],[10],[15]     101 [2],[10],[15]   89 [1],[5],[14]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 17            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5 5    
Investments, at fair value, ending balance 94 [2],[10]     94 [2],[10]   5 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,852 7,852    
Investments, at fair value, ending balance 8,056 [2],[10]     8,056 [2],[10]   7,852 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     4,061 4,061    
Investments, at fair value, ending balance 4,167 [2],[10]     4,167 [2],[10]   4,061 [1],[5],[16]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,065 2,065    
Investments, at fair value, ending balance 2,119 [2],[10]     2,119 [2],[10]   2,065 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     1,823 1,823    
Investments, at fair value, ending balance 1,870 [2],[10]     1,870 [2],[10]   1,823 [1],[5],[16]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     1,135 1,135    
Investments, at fair value, ending balance 1,165 [2],[10]     1,165 [2],[10]   1,135 [1],[5],[16]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     943 943    
Investments, at fair value, ending balance 967 [2],[10]     967 [2],[10]   943 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     928 928    
Investments, at fair value, ending balance 952 [2],[10]     952 [2],[10]   928 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     888 888    
Investments, at fair value, ending balance 912 [2],[10]     912 [2],[10]   888 [1],[5]
Investment, Identifier [Axis]: Encorevet Group LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     203 203    
Investments, at fair value, ending balance 85 [2],[10]     85 [2],[10]   203 [1],[5]
Investment, Identifier [Axis]: Energy Worldnet, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 52     52    
Investment, Identifier [Axis]: Entomo Brands Acquisitions, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,389 4,389    
Investments, at fair value, ending balance 4,355 [2],[10]     4,355 [2],[10]   4,389 [1],[5],[9]
Investment, Identifier [Axis]: Entomo Brands Acquisitions, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     30 30    
Investments, at fair value, ending balance 1,263 [2],[10]     1,263 [2],[10]   30 [1],[5]
Investment, Identifier [Axis]: Entomo Brands Acquisitions, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,263 1,263    
Investments, at fair value, ending balance 30 [2],[10]     30 [2],[10]   1,263 [1],[5]
Investment, Identifier [Axis]: Envernus, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,131 5,131    
Investments, at fair value, ending balance 5,251 [2],[10]     5,251 [2],[10]   5,131 [1],[5],[9]
Investment, Identifier [Axis]: Envernus, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5 5    
Investments, at fair value, ending balance 7 [2],[10]     7 [2],[10]   5 [1],[5]
Investment, Identifier [Axis]: Envernus, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Equity Methods, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 19,730     19,730    
Investment, Identifier [Axis]: Equity Methods, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (18)     (18)    
Investment, Identifier [Axis]: Equity Methods, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (23)     (23)    
Investment, Identifier [Axis]: Espresso Bidco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 18,251     18,251    
Investment, Identifier [Axis]: Espresso Bidco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Espresso Bidco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Essential Services Holdings Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     11,399 11,399    
Investments, at fair value, ending balance 11,399 [2],[10]     11,399 [2],[10]   11,399 [1],[5]
Investment, Identifier [Axis]: Essential Services Holdings Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (14) (14)    
Investments, at fair value, ending balance 159 [2],[10]     159 [2],[10]   (14) [1],[5],[12]
Investment, Identifier [Axis]: Essential Services Holdings Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (23) (23)    
Investments, at fair value, ending balance (23) [2],[10],[13]     (23) [2],[10],[13]   (23) [1],[5],[12]
Investment, Identifier [Axis]: Evergreen IX Borrower 2023, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,869 4,869    
Investments, at fair value, ending balance 4,881 [2],[10]     4,881 [2],[10]   4,869 [1],[5],[9]
Investment, Identifier [Axis]: Evergreen IX Borrower 2023, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,438 4,438    
Investments, at fair value, ending balance 4,449 [2],[10]     4,449 [2],[10]   4,438 [1],[5]
Investment, Identifier [Axis]: Evergreen IX Borrower 2023, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (4) [1],[5],[12]
Investment, Identifier [Axis]: Excelitas Technologies Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (84) (84)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (84) [1],[5],[12]
Investment, Identifier [Axis]: Excelitas Technologies Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     9,920 9,920    
Investments, at fair value, ending balance 10,022 [2],[10]     10,022 [2],[10]   9,920 [1],[5],[9]
Investment, Identifier [Axis]: Excelitas Technologies Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[30]     1,901 1,901    
Investments, at fair value, ending balance 2,016 [2],[10],[25],[32]     2,016 [2],[10],[25],[32]   1,901 [1],[5],[8],[9],[30]
Investment, Identifier [Axis]: Excelitas Technologies Corp., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (4) [1],[5],[12]
Investment, Identifier [Axis]: Excelitas Technologies Corp., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance [1],[5],[12]           (3)
Investment, Identifier [Axis]: FPG Intermediate Holdco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     10,992 10,992    
Investments, at fair value, ending balance 12,467 [2],[10],[15],[22]     12,467 [2],[10],[15],[22]   10,992 [1],[5],[14]
Investment, Identifier [Axis]: FPG Intermediate Holdco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     6,084 6,084    
Investments, at fair value, ending balance 909 [2],[10],[15]     909 [2],[10],[15]   6,084 [1],[5],[14]
Investment, Identifier [Axis]: FPG Intermediate Holdco, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     126 126    
Investments, at fair value, ending balance 128 [2],[10],[15]     128 [2],[10],[15]   126 [1],[5],[14]
Investment, Identifier [Axis]: FR Vision Holdings, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     471 471    
Investments, at fair value, ending balance [1],[5]           471
Investment, Identifier [Axis]: FR Vision Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,070 1,070    
Investments, at fair value, ending balance [1],[5],[9]           1,070
Investment, Identifier [Axis]: FR Vision Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     90 90    
Investments, at fair value, ending balance [1],[5]           90
Investment, Identifier [Axis]: FR Vision Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: FSS Buyer LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     7,666 7,666    
Investments, at fair value, ending balance 6,898 [2],[10]     6,898 [2],[10]   7,666 [1],[5],[17]
Investment, Identifier [Axis]: FSS Buyer LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 22 [2],[10]     22 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[30]     11,272 11,272    
Investments, at fair value, ending balance 11,203 [2],[10],[25],[28],[32]     11,203 [2],[10],[25],[28],[32]   11,272 [1],[5],[7],[8],[9],[30]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     4,074 4,074    
Investments, at fair value, ending balance 4,049 [2],[10],[25],[28],[32]     4,049 [2],[10],[25],[28],[32]   4,074 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     2,774 2,774    
Investments, at fair value, ending balance 2,758 [2],[10],[25],[28],[32]     2,758 [2],[10],[25],[28],[32]   2,774 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     2,642 2,642    
Investments, at fair value, ending balance 2,626 [2],[10],[25],[28],[32]     2,626 [2],[10],[25],[28],[32]   2,642 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[19]     1,105 1,105    
Investments, at fair value, ending balance 1,105 [2],[10],[20],[25],[28]     1,105 [2],[10],[20],[25],[28]   1,105 [1],[5],[7],[8],[19]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9]     554 554    
Investments, at fair value, ending balance 554 [2],[10],[25],[28]     554 [2],[10],[25],[28]   554 [1],[5],[7],[8],[9]
Investment, Identifier [Axis]: FYI Optical Acquisitions, Inc. & FYI USA, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     481 481    
Investments, at fair value, ending balance 478 [2],[10],[25],[28],[32]     478 [2],[10],[25],[28],[32]   481 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: Filevine, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     8,344 8,344    
Investments, at fair value, ending balance 8,525 [2],[10],[15],[20]     8,525 [2],[10],[15],[20]   8,344 [1],[5],[14],[19]
Investment, Identifier [Axis]: Filevine, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Filevine, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,992 3,992    
Investments, at fair value, ending balance 4,987 [2],[10]     4,987 [2],[10]   3,992 [1],[5]
Investment, Identifier [Axis]: Filevine, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     234 234    
Investments, at fair value, ending balance 291 [2],[10]     291 [2],[10]   234 [1],[5]
Investment, Identifier [Axis]: Filevine, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     485 485    
Investments, at fair value, ending balance 633 [2],[10]     633 [2],[10]   485 [1],[5]
Investment, Identifier [Axis]: Financial Information Technologies, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17]     34,626 34,626    
Investments, at fair value, ending balance [1],[5],[9],[16],[17]           34,626
Investment, Identifier [Axis]: Financial Information Technologies, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     19,894 19,894    
Investments, at fair value, ending balance [1],[5],[14]           19,894
Investment, Identifier [Axis]: Financial Information Technologies, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Financial Information Technologies, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,221 2,221    
Investments, at fair value, ending balance [1],[5],[9]           2,221
Investment, Identifier [Axis]: Financial Information Technologies, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Financial Information Technologies, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 34,278     34,278    
Investment, Identifier [Axis]: Financial Information Technologies, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 22,744     22,744    
Investment, Identifier [Axis]: Financial Information Technologies, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Financial Information Technologies, LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,199     2,199    
Investment, Identifier [Axis]: Financial Information Technologies, LLC., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (3)     (3)    
Investment, Identifier [Axis]: Finastra USA, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,393 5,393    
Investments, at fair value, ending balance 5,332 [2],[10],[25],[31]     5,332 [2],[10],[25],[31]   5,393 [1],[5],[9]
Investment, Identifier [Axis]: Finastra USA, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     46 46    
Investments, at fair value, ending balance 20 [2],[10],[25],[31]     20 [2],[10],[25],[31]   46 [1],[5]
Investment, Identifier [Axis]: FirstUp, Inc. Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     346 346    
Investments, at fair value, ending balance [1],[5]           346
Investment, Identifier [Axis]: FirstUp, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 228     228    
Investment, Identifier [Axis]: FirstUp, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     12,863 12,863    
Investments, at fair value, ending balance 12,994 [2],[10],[20]     12,994 [2],[10],[20]   12,863 [1],[5],[14],[19]
Investment, Identifier [Axis]: FirstUp, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     1,226 1,226    
Investments, at fair value, ending balance 1,239 [2],[10]     1,239 [2],[10]   1,226 [1],[5],[9],[14]
Investment, Identifier [Axis]: FirstUp, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   (4) [1],[5],[12]
Investment, Identifier [Axis]: FirstUp, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 29     29    
Investment, Identifier [Axis]: Flash Topco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[17]     16,240 16,240    
Investments, at fair value, ending balance 16,793 [2],[10]     16,793 [2],[10]   16,240 [1],[6],[17]
Investment, Identifier [Axis]: Flash Topco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     136 136    
Investments, at fair value, ending balance 3,352 [2],[10]     3,352 [2],[10]   136 [1],[5]
Investment, Identifier [Axis]: Flash Topco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     74 74    
Investments, at fair value, ending balance 118 [2],[10]     118 [2],[10]   74 [1],[5]
Investment, Identifier [Axis]: Fleet Farm Group LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     0 0    
Gross additions       29,147    
Gross reductions       0    
Net change in unrealized appreciation (depreciation)       523    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 29,670     29,670   0
Interest, dividend and fee income       239    
Investment, Identifier [Axis]: Fleet Farm Group, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2] 24,503     24,503    
Investment, Identifier [Axis]: Fleet Farm Group, LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[18],[21]     31,866 31,866    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   31,866 [1],[5],[6],[18],[21]
Investment, Identifier [Axis]: Fleet Farm Group, LLC, Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 5,167     5,167    
Investment, Identifier [Axis]: Fortis Solutions Group LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[17],[18],[19]     50,501 50,501    
Investments, at fair value, ending balance [1],[5],[6],[16],[17],[18],[19]           50,501
Investment, Identifier [Axis]: Fortis Solutions Group LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     70 70    
Investments, at fair value, ending balance [1],[5]           70
Investment, Identifier [Axis]: Fortis Solutions Group LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     138 138    
Investments, at fair value, ending balance [1],[5]           138
Investment, Identifier [Axis]: Fortis Solutions Group LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     152 152    
Investments, at fair value, ending balance [1],[5]           152
Investment, Identifier [Axis]: Fortis Solutions Group, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,700     1,700    
Investment, Identifier [Axis]: Fortis Solutions Group, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 141     141    
Investment, Identifier [Axis]: Fortis Solutions Group, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 152     152    
Investment, Identifier [Axis]: Fortis Solutions Group, LLC^, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11],[20] 51,729     51,729    
Investment, Identifier [Axis]: Franchise Brands plc, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[26],[29],[30],[43]     118 118    
Investments, at fair value, ending balance [1],[5],[8],[26],[29],[30],[43]           118
Investment, Identifier [Axis]: Freddy's Frozen Custard LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     648 648    
Investments, at fair value, ending balance 838 [2],[10]     838 [2],[10]   648 [1],[5]
Investment, Identifier [Axis]: Freddy's Frozen Custard LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,397 1,397    
Investments, at fair value, ending balance 1,387 [2],[10]     1,387 [2],[10]   1,397 [1],[5],[9]
Investment, Identifier [Axis]: Freddy's Frozen Custard LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     10 10    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   10 [1],[5]
Investment, Identifier [Axis]: G & H Wire Company, Inc            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     0 0    
Gross additions       6,623    
Gross reductions       0    
Net change in unrealized appreciation (depreciation)       398    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 7,021     7,021   0
Interest, dividend and fee income       176    
Investment, Identifier [Axis]: G & H Wire Company, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: G & H Wire Company, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 4,209     4,209    
Investment, Identifier [Axis]: G & H Wire Company, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     6,564 6,564    
Investments, at fair value, ending balance 2,812 [2],[10],[15]     2,812 [2],[10],[15]   6,564 [1],[5],[14],[21]
Investment, Identifier [Axis]: G & H Wire Company, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     34 34    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   34 [1],[5],[14],[21]
Investment, Identifier [Axis]: GFP Atlantic Holdco 2, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,078 1,078    
Investments, at fair value, ending balance 1,070 [2],[10]     1,070 [2],[10]   1,078 [1],[5],[9]
Investment, Identifier [Axis]: GFP Atlantic Holdco 2, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: GHX Ultimate Parent Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 53,884     53,884    
Investment, Identifier [Axis]: GHX Ultimate Parent Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: GS Acquisitionco, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     952 952    
Investments, at fair value, ending balance 846 [2],[10]     846 [2],[10]   952 [1],[5]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17],[19]     121,514 121,514    
Investments, at fair value, ending balance 121,779 [2],[10],[11],[20]     121,779 [2],[10],[11],[20]   121,514 [1],[5],[9],[16],[17],[19]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     65 65    
Investments, at fair value, ending balance 123 [2],[10]     123 [2],[10]   65 [1],[5]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance 41 [2],[10]     41 [2],[10]   (3) [1],[5],[12]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     46,202 46,202    
Investments, at fair value, ending balance 51,707 [2],[10],[27]     51,707 [2],[10],[27]   46,202 [1],[5],[26]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     5,741 5,741    
Investments, at fair value, ending balance 6,425 [2],[10],[27]     6,425 [2],[10],[27]   5,741 [1],[5],[26]
Investment, Identifier [Axis]: GS Acquisitionco, Inc., Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     120 120    
Investments, at fair value, ending balance 134 [2],[10],[27]     134 [2],[10],[27]   120 [1],[5],[26]
Investment, Identifier [Axis]: GTIV, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     72,000 72,000    
Investments, at fair value, ending balance 71,446 [2],[10],[11]     71,446 [2],[10],[11]   72,000 [1],[5]
Investment, Identifier [Axis]: GTIV, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance (3) [2],[10],[13]     (3) [2],[10],[13]   (3) [1],[5],[12]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     140 140    
Investments, at fair value, ending balance 168 [2],[10]     168 [2],[10]   140 [1],[5]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     5,049 5,049    
Investments, at fair value, ending balance 8,970 [2],[10],[15]     8,970 [2],[10],[15]   5,049 [1],[5],[9],[14]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     3,296 3,296    
Investments, at fair value, ending balance 5,264 [2],[10],[15]     5,264 [2],[10],[15]   3,296 [1],[5],[9],[14]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     605 605    
Investments, at fair value, ending balance 3,441 [2],[10],[15]     3,441 [2],[10],[15]   605 [1],[5],[14]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     424 424    
Investments, at fair value, ending balance 1,026 [2],[10],[15]     1,026 [2],[10],[15]   424 [1],[5],[14]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance 630 [2],[10],[15]     630 [2],[10],[15]   (2) [1],[5],[12]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 438 [2],[10],[15]     438 [2],[10],[15]   0 [1],[5],[12]
Investment, Identifier [Axis]: GTY Technology Holdings, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 539     539    
Investment, Identifier [Axis]: Gainsight, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     17,981 17,981    
Investments, at fair value, ending balance 14,171 [2],[10],[20]     14,171 [2],[10],[20]   17,981 [1],[5],[14],[19]
Investment, Identifier [Axis]: Gainsight, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     128 128    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   128 [1],[5],[14]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2 2    
Investments, at fair value, ending balance 2 [2],[10]     2 [2],[10]   2 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     369 369    
Investments, at fair value, ending balance 337 [2],[10],[27]     337 [2],[10],[27]   369 [1],[5],[26]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     9,235 9,235    
Investments, at fair value, ending balance 9,154 [2],[10]     9,154 [2],[10]   9,235 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     6,391 6,391    
Investments, at fair value, ending balance 6,342 [2],[10]     6,342 [2],[10]   6,391 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     989 989    
Investments, at fair value, ending balance 982 [2],[10]     982 [2],[10]   989 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     889 889    
Investments, at fair value, ending balance 882 [2],[10]     882 [2],[10]   889 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     623 623    
Investments, at fair value, ending balance 619 [2],[10]     619 [2],[10]   623 [1],[5]
Investment, Identifier [Axis]: Georgica Pine Clothiers, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2 2    
Investments, at fair value, ending balance 2 [2],[10]     2 [2],[10]   2 [1],[5]
Investment, Identifier [Axis]: Gimlet Bidco GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[44]     1,079 1,079    
Investments, at fair value, ending balance 1,152 [2],[10],[25],[32],[45]     1,152 [2],[10],[25],[32],[45]   1,079 [1],[5],[8],[30],[44]
Investment, Identifier [Axis]: Gimlet Bidco GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[44]     76 76    
Investments, at fair value, ending balance 327 [2],[10],[25],[32],[45]     327 [2],[10],[25],[32],[45]   76 [1],[5],[8],[30],[44]
Investment, Identifier [Axis]: Go Car Wash Parent, Corp., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     19 19    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   19 [1],[5]
Investment, Identifier [Axis]: Go Car Wash Parent, Corp., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     3,136 3,136    
Investments, at fair value, ending balance 3,534 [2],[10],[27]     3,534 [2],[10],[27]   3,136 [1],[5],[26]
Investment, Identifier [Axis]: Goldcup 31018 AB, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30],[46]     14,283 14,283    
Investments, at fair value, ending balance 14,732 [2],[10],[15],[25],[32],[47]     14,732 [2],[10],[15],[25],[32],[47]   14,283 [1],[5],[8],[9],[14],[30],[46]
Investment, Identifier [Axis]: Goldcup 31018 AB, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[46]     1,332 1,332    
Investments, at fair value, ending balance 1,324 [2],[10],[15],[25],[32],[47]     1,324 [2],[10],[15],[25],[32],[47]   1,332 [1],[5],[8],[14],[30],[46]
Investment, Identifier [Axis]: Goldcup 31018 AB, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[46]     0 0    
Investments, at fair value, ending balance 220 [2],[10],[25],[32],[47]     220 [2],[10],[25],[32],[47]   0 [1],[5],[8],[12],[30],[46]
Investment, Identifier [Axis]: Graphpad Software, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     8,869 8,869    
Investments, at fair value, ending balance 8,803 [2],[10]     8,803 [2],[10]   8,869 [1],[5]
Investment, Identifier [Axis]: Graphpad Software, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Graphpad Software, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     222 222    
Investments, at fair value, ending balance 220 [2],[10]     220 [2],[10]   222 [1],[5]
Investment, Identifier [Axis]: Gurobi Optimization, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     709 709    
Investments, at fair value, ending balance 777 [2],[10]     777 [2],[10]   709 [1],[5]
Investment, Identifier [Axis]: Gurobi Optimization, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     52,235 52,235    
Investments, at fair value, ending balance 50,565 [2],[10]     50,565 [2],[10]   52,235 [1],[5]
Investment, Identifier [Axis]: Gurobi Optimization, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (44) (44)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (44) [1],[5],[12]
Investment, Identifier [Axis]: HS Spa Holdings, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     730 730    
Investments, at fair value, ending balance 634 [2],[10]     634 [2],[10]   730 [1],[5]
Investment, Identifier [Axis]: HS Spa Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     11,550 11,550    
Investments, at fair value, ending balance 11,462 [2],[10]     11,462 [2],[10]   11,550 [1],[5],[9]
Investment, Identifier [Axis]: HS Spa Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     64 64    
Investments, at fair value, ending balance 687 [2],[10]     687 [2],[10]   64 [1],[5]
Investment, Identifier [Axis]: HS Spa Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 44 [2],[10]     44 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: HSI Halo Acquisition, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     58 58    
Investments, at fair value, ending balance 98 [2],[10]     98 [2],[10]   58 [1],[5]
Investment, Identifier [Axis]: HSI Halo Acquisition, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     233 233    
Investments, at fair value, ending balance 251 [2],[10],[27]     251 [2],[10],[27]   233 [1],[5],[26]
Investment, Identifier [Axis]: Harri US LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     711 711    
Investments, at fair value, ending balance 702 [2],[10]     702 [2],[10]   711 [1],[5]
Investment, Identifier [Axis]: Harri US LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     1,211 1,211    
Investments, at fair value, ending balance 1,216 [2],[10],[15],[20]     1,216 [2],[10],[15],[20]   1,211 [1],[5],[14],[19]
Investment, Identifier [Axis]: Harri US LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     821 821    
Investments, at fair value, ending balance 822 [2],[10],[15]     822 [2],[10],[15]   821 [1],[5],[14]
Investment, Identifier [Axis]: Harri US LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     797 797    
Investments, at fair value, ending balance 798 [2],[10],[15]     798 [2],[10],[15]   797 [1],[5],[14]
Investment, Identifier [Axis]: Harri US LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   (2) [1],[5],[12]
Investment, Identifier [Axis]: Harri US LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 1,490     1,490    
Investment, Identifier [Axis]: Harri US LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (41) (41)    
Investments, at fair value, ending balance [1],[5],[12]           (41)
Investment, Identifier [Axis]: Harri US LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (120)     (120)    
Investment, Identifier [Axis]: Harri US LLC, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     587 587    
Investments, at fair value, ending balance 586 [2],[10]     586 [2],[10]   587 [1],[5]
Investment, Identifier [Axis]: Harri US LLC, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,342 1,342    
Investments, at fair value, ending balance 1,407 [2],[10]     1,407 [2],[10]   1,342 [1],[5]
Investment, Identifier [Axis]: Harri US LLC, Warrant 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     196 196    
Investments, at fair value, ending balance 195 [2],[10]     195 [2],[10]   196 [1],[5]
Investment, Identifier [Axis]: Harri US LLC, Warrant 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     132 132    
Investments, at fair value, ending balance 137 [2],[10]     137 [2],[10]   132 [1],[5]
Investment, Identifier [Axis]: Harri US LLC, Warrant 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Harri US LLC, Warrant 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 120     120    
Investment, Identifier [Axis]: Health Buyer, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,853 3,853    
Investments, at fair value, ending balance 3,873 [2],[10]     3,873 [2],[10]   3,853 [1],[5],[9]
Investment, Identifier [Axis]: Health Buyer, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,776 1,776    
Investments, at fair value, ending balance 1,768 [2],[10]     1,768 [2],[10]   1,776 [1],[5],[9]
Investment, Identifier [Axis]: Health Buyer, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     714 714    
Investments, at fair value, ending balance 888 [2],[10]     888 [2],[10]   714 [1],[5]
Investment, Identifier [Axis]: Health Buyer, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 129 [2],[10]     129 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Health Buyer, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: HealthEdge Software, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     19,218 19,218    
Investments, at fair value, ending balance [1],[5]           19,218
Investment, Identifier [Axis]: HealthEdge Software, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (26) (26)    
Investments, at fair value, ending balance [1],[5],[12]           (26)
Investment, Identifier [Axis]: HealthEdge Software, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (43) (43)    
Investments, at fair value, ending balance [1],[5],[12]           (43)
Investment, Identifier [Axis]: Heartland Veterinary Partners LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,507 2,507    
Investments, at fair value, ending balance 2,512 [2],[10]     2,512 [2],[10]   2,507 [1],[5],[9]
Investment, Identifier [Axis]: Heartland Veterinary Partners LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,190 1,190    
Investments, at fair value, ending balance 1,193 [2],[10]     1,193 [2],[10]   1,190 [1],[5],[9]
Investment, Identifier [Axis]: Heartland Veterinary Partners LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Higginbotham Insurance Agency, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,093 8,093    
Investments, at fair value, ending balance 7,952 [2],[10]     7,952 [2],[10]   8,093 [1],[5],[9]
Investment, Identifier [Axis]: Higginbotham Insurance Agency, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     220 220    
Investments, at fair value, ending balance 639 [2],[10]     639 [2],[10]   220 [1],[5]
Investment, Identifier [Axis]: High Bar Brands Operating, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,435 1,435    
Investments, at fair value, ending balance 1,426 [2],[10]     1,426 [2],[10]   1,435 [1],[5],[9]
Investment, Identifier [Axis]: High Bar Brands Operating, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     299 299    
Investments, at fair value, ending balance 297 [2],[10]     297 [2],[10]   299 [1],[5],[9]
Investment, Identifier [Axis]: High Bar Brands Operating, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     254 254    
Investments, at fair value, ending balance 251 [2],[10]     251 [2],[10]   254 [1],[5]
Investment, Identifier [Axis]: High Bar Brands Operating, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 11 [2],[10]     11 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Hopdoddy Holdings, LLC, LLC units 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     217 217    
Investments, at fair value, ending balance 271 [2],[10]     271 [2],[10]   217 [1],[5]
Investment, Identifier [Axis]: Hopdoddy Holdings, LLC, LLC units 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     48 48    
Investments, at fair value, ending balance 60 [2],[10]     60 [2],[10]   48 [1],[5]
Investment, Identifier [Axis]: Hornet Security Holding GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30],[44]     748 748    
Investments, at fair value, ending balance 799 [2],[10],[25],[32],[45]     799 [2],[10],[25],[32],[45]   748 [1],[5],[8],[9],[14],[30],[44]
Investment, Identifier [Axis]: Hornet Security Holding GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30],[44]     498 498    
Investments, at fair value, ending balance 533 [2],[10],[25],[32],[45]     533 [2],[10],[25],[32],[45]   498 [1],[5],[8],[9],[14],[30],[44]
Investment, Identifier [Axis]: Hornet Security Holding GMBH, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[44]     0 0    
Investments, at fair value, ending balance 15 [2],[10],[25],[32],[45]     15 [2],[10],[25],[32],[45]   0 [1],[5],[8],[12],[30],[44]
Investment, Identifier [Axis]: Hornet Security Holding GMBH, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[44]     0 0    
Investments, at fair value, ending balance 112 [2],[10],[25],[32],[45]     112 [2],[10],[25],[32],[45]   0 [1],[5],[8],[12],[30],[44]
Investment, Identifier [Axis]: HuFriedy Group Acquisition, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,851 7,851    
Investments, at fair value, ending balance 7,871 [2],[10]     7,871 [2],[10]   7,851 [1],[5]
Investment, Identifier [Axis]: HuFriedy Group Acquisition, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (9) (9)    
Investments, at fair value, ending balance 52 [2],[10]     52 [2],[10]   (9) [1],[5],[12]
Investment, Identifier [Axis]: HuFriedy Group Acquisition, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (17) (17)    
Investments, at fair value, ending balance 1,523 [2],[10]     1,523 [2],[10]   (17) [1],[5],[12]
Investment, Identifier [Axis]: Hyland Software, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[17]     47,242 47,242    
Investments, at fair value, ending balance 46,886 [2],[10],[11]     46,886 [2],[10],[11]   47,242 [1],[5],[9],[16],[17]
Investment, Identifier [Axis]: Hyland Software, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: ICIMS, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     11,845 11,845    
Investments, at fair value, ending balance 11,854 [2],[10],[11]     11,854 [2],[10],[11]   11,845 [1],[5],[9],[14]
Investment, Identifier [Axis]: ICIMS, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     80 80    
Investments, at fair value, ending balance 32 [2],[10]     32 [2],[10]   80 [1],[5]
Investment, Identifier [Axis]: ICIMS, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (103) (103)    
Investments, at fair value, ending balance [1],[5],[12]           (103)
Investment, Identifier [Axis]: IG Investments Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     9,122 9,122    
Investments, at fair value, ending balance 12,908 [2],[10],[11]     12,908 [2],[10],[11]   9,122 [1],[5],[17]
Investment, Identifier [Axis]: IG Investments Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     782 782    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   782 [1],[5],[17]
Investment, Identifier [Axis]: IG Investments Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: IMPLUS Footcare, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     27,450 27,450    
Investments, at fair value, ending balance 16,207 [2],[10],[15],[22]     16,207 [2],[10],[15],[22]   27,450 [1],[5],[14]
Investment, Identifier [Axis]: IMPLUS Footcare, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     4,688 4,688    
Investments, at fair value, ending balance 2,768 [2],[10],[15],[22]     2,768 [2],[10],[15],[22]   4,688 [1],[5],[14]
Investment, Identifier [Axis]: IMPLUS Footcare, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[14]     675 675    
Investments, at fair value, ending balance 399 [2],[10],[15],[22]     399 [2],[10],[15],[22]   675 [1],[5],[6],[14]
Investment, Identifier [Axis]: IMPLUS Footcare, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 1,536     1,536    
Investment, Identifier [Axis]: IQN Holding Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17],[18]     22,887 22,887    
Investments, at fair value, ending balance 22,598 [2],[10],[11],[15]     22,598 [2],[10],[11],[15]   22,887 [1],[5],[17],[18]
Investment, Identifier [Axis]: IQN Holding Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     52 52    
Investments, at fair value, ending balance 164 [2],[10]     164 [2],[10]   52 [1],[5]
Investment, Identifier [Axis]: IQN Holding Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 3,994     3,994    
Investment, Identifier [Axis]: IQN Holding Corp., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (6)     (6)    
Investment, Identifier [Axis]: Icefall Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,407 1,407    
Investments, at fair value, ending balance 1,407 [2],[10]     1,407 [2],[10]   1,407 [1],[5],[9]
Investment, Identifier [Axis]: Icefall Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Illumifin Corporation, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     4,018 4,018    
Investments, at fair value, ending balance 4,426 [2],[10],[15]     4,426 [2],[10],[15]   4,018 [1],[5],[9],[14]
Investment, Identifier [Axis]: Impartner, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     217 217    
Investments, at fair value, ending balance [1],[5]           217
Investment, Identifier [Axis]: Impartner, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 200     200    
Investment, Identifier [Axis]: Imperial Optical Midco Inc, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     40,558 40,558    
Investments, at fair value, ending balance [1],[5]           40,558
Investment, Identifier [Axis]: Imperial Optical Midco Inc, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (282) (282)    
Investments, at fair value, ending balance [1],[5],[12]           (282)
Investment, Identifier [Axis]: Imperial Optical Midco Inc, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (1,502) (1,502)    
Investments, at fair value, ending balance [1],[5],[12]           (1,502)
Investment, Identifier [Axis]: Imperial Optical Midco Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     93,864 93,864 0 0
Gross additions           94,556
Gross reductions           0
Net change in unrealized appreciation (depreciation)           (692)
Net realized gain (loss)           0
Investments, at fair value, ending balance           93,864
Interest, dividend and fee income           1,008
Investment, Identifier [Axis]: Imperial Optical Midco, Inc, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     55,090 55,090    
Investments, at fair value, ending balance 60,835 [2],[10]     60,835 [2],[10]   55,090 [1],[5]
Investment, Identifier [Axis]: Inhabit IQ Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,488 1,488    
Investments, at fair value, ending balance 663 [2],[10]     663 [2],[10]   1,488 [1],[5]
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[17]     37,583 37,583    
Investments, at fair value, ending balance 6,890 [2],[10]     6,890 [2],[10]   37,583 [1],[9],[17]
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,166 1,166    
Investments, at fair value, ending balance [1],[5],[9]           1,166
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     614 614    
Investments, at fair value, ending balance [1],[5],[9]           614
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9]     680 680    
Investments, at fair value, ending balance [1],[9]           680
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[18]     21,694 21,694    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   21,694 [1],[5],[16],[18]
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     15,607 15,607    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   15,607 [1],[5],[16]
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[19]     21,366 21,366    
Investments, at fair value, ending balance [1],[6],[19]           21,366
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[16],[18]     7,460 7,460    
Investments, at fair value, ending balance [1],[6],[16],[18]           7,460
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,988 3,988    
Investments, at fair value, ending balance [1],[5],[9]           3,988
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[18]     1,745 1,745    
Investments, at fair value, ending balance [1],[5],[9],[18]           1,745
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[18]     1,478 1,478    
Investments, at fair value, ending balance [1],[5],[9],[18]           1,478
Investment, Identifier [Axis]: Inhabit IQ Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[18]     1,461 1,461    
Investments, at fair value, ending balance [1],[5],[9],[18]           1,461
Investment, Identifier [Axis]: Inhance Technologies Holdings LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Inhance Technologies Holdings LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,902 4,902    
Investments, at fair value, ending balance [1],[5]           4,902
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[18]     12,257 12,257    
Investments, at fair value, ending balance [1],[5],[9],[14],[18]           12,257
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[14],[17],[18]     11,130 11,130    
Investments, at fair value, ending balance [1],[14],[17],[18]           11,130
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     2,165 2,165    
Investments, at fair value, ending balance [1],[5],[9],[14]           2,165
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     251 251    
Investments, at fair value, ending balance [1],[5],[14]           251
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 195     195    
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 12,943     12,943    
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 11,753     11,753    
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 2,287     2,287    
Investment, Identifier [Axis]: Inhance Technologies Holdings, LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 265     265    
Investment, Identifier [Axis]: Integrated Specialty Coverages, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,051 5,051    
Investments, at fair value, ending balance 10,137 [2],[10]     10,137 [2],[10]   5,051 [1],[5],[9]
Investment, Identifier [Axis]: Integrated Specialty Coverages, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Integrated Specialty Coverages, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,008 1,008    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   1,008 [1],[5]
Investment, Identifier [Axis]: Integrity Marketing Acquisition, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17]     44,110 44,110    
Investments, at fair value, ending balance 48,037 [2],[10],[11]     48,037 [2],[10],[11]   44,110 [1],[5],[16],[17]
Investment, Identifier [Axis]: Integrity Marketing Acquisition, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (4) [1],[5],[12]
Investment, Identifier [Axis]: Integrity Marketing Acquisition, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (39) (39)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (39) [1],[5],[12]
Investment, Identifier [Axis]: Internet Truckstop Group, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     402 402    
Investments, at fair value, ending balance 410 [2],[10]     410 [2],[10]   402 [1],[5]
Investment, Identifier [Axis]: Internet Truckstop Group, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     28,346 28,346    
Investments, at fair value, ending balance 28,345 [2],[11]     28,345 [2],[11]   28,346 [1],[5],[16]
Investment, Identifier [Axis]: Internet Truckstop Group, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     12,427 12,427    
Investments, at fair value, ending balance 12,427 [2],[10],[11]     12,427 [2],[10],[11]   12,427 [1],[5],[17]
Investment, Identifier [Axis]: Internet Truckstop Group, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance (3) [2],[10],[13]     (3) [2],[10],[13]   (3) [1],[5],[12]
Investment, Identifier [Axis]: Inventus Power, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Inventus Power, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     276 276    
Investments, at fair value, ending balance 276 [2],[10]     276 [2],[10]   276 [1],[5]
Investment, Identifier [Axis]: Inventus Power, Inc., LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     61 61    
Investments, at fair value, ending balance [1],[5]           61
Investment, Identifier [Axis]: Inventus Power, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 61     61    
Investment, Identifier [Axis]: Inventus Power, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     20 20    
Investments, at fair value, ending balance 56 [2],[10]     56 [2],[10]   20 [1],[5]
Investment, Identifier [Axis]: Island Bidco AB, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30],[46]     10,768 10,768    
Investments, at fair value, ending balance 12,020 [2],[10],[15],[25],[32],[47]     12,020 [2],[10],[15],[25],[32],[47]   10,768 [1],[5],[8],[9],[14],[30],[46]
Investment, Identifier [Axis]: Island Bidco AB, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[46]     4,791 4,791    
Investments, at fair value, ending balance 4,917 [2],[10],[15],[25],[47]     4,917 [2],[10],[15],[25],[47]   4,791 [1],[5],[8],[9],[14],[46]
Investment, Identifier [Axis]: Island Bidco AB, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[46]     3,535 3,535    
Investments, at fair value, ending balance 3,628 [2],[10],[15],[25],[47]     3,628 [2],[10],[15],[25],[47]   3,535 [1],[5],[8],[14],[46]
Investment, Identifier [Axis]: Island Bidco AB, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[46]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[32],[47]     0 [2],[10],[25],[32],[47]   0 [1],[5],[8],[12],[30],[46]
Investment, Identifier [Axis]: Island Bidco AB, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[46]     0 0    
Investments, at fair value, ending balance 50 [2],[10],[25],[47]     50 [2],[10],[25],[47]   0 [1],[5],[8],[46]
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[19]     22,154 22,154    
Investments, at fair value, ending balance 37,932 [2],[10],[11],[20]     37,932 [2],[10],[11],[20]   22,154 [1],[5],[9],[16],[19]
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     5,346 5,346    
Investments, at fair value, ending balance 8,167 [2],[10]     8,167 [2],[10]   5,346 [1],[5],[17]
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,171 5,171    
Investments, at fair value, ending balance 103 [2],[10]     103 [2],[10]   5,171 [1],[5],[9]
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,005 5,005    
Investments, at fair value, ending balance [1],[5],[9]           5,005
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     159 159    
Investments, at fair value, ending balance [1],[5]           159
Investment, Identifier [Axis]: J.S. Held Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (6) (6)    
Investments, at fair value, ending balance [1],[5],[12]           (6)
Investment, Identifier [Axis]: JHC Investment Intermediate Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     188 188    
Investments, at fair value, ending balance 1,516 [2],[10]     1,516 [2],[10]   188 [1],[5]
Investment, Identifier [Axis]: JHC Investment Intermediate Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,351 1,351    
Investments, at fair value, ending balance 1,217 [2],[10],[15]     1,217 [2],[10],[15]   1,351 [1],[5],[14]
Investment, Identifier [Axis]: JHC Investment Intermediate Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     684 684    
Investments, at fair value, ending balance 908 [2],[10],[15]     908 [2],[10],[15]   684 [1],[5],[14],[21]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     17,889 17,889    
Investments, at fair value, ending balance 17,754 [2],[10],[11]     17,754 [2],[10],[11]   17,889 [1],[5],[16]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,533     3,533    
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,179 5,179    
Investments, at fair value, ending balance 6,904 [2],[10]     6,904 [2],[10]   5,179 [1],[5],[9]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,951 4,951    
Investments, at fair value, ending balance 5,140 [2],[10]     5,140 [2],[10]   4,951 [1],[5]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,714 3,714    
Investments, at fair value, ending balance 4,913 [2],[10]     4,913 [2],[10]   3,714 [1],[5]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,797 2,797    
Investments, at fair value, ending balance 2,771 [2],[10]     2,771 [2],[10]   2,797 [1],[5]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,659 1,659    
Investments, at fair value, ending balance 1,646 [2],[10]     1,646 [2],[10]   1,659 [1],[5],[9]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     732 732    
Investments, at fair value, ending balance 728 [2],[10]     728 [2],[10]   732 [1],[5],[9]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     695 695    
Investments, at fair value, ending balance 690 [2],[10]     690 [2],[10]   695 [1],[5],[9]
Investment, Identifier [Axis]: JHCC Holdings LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     66 66    
Investments, at fair value, ending balance 60 [2],[10]     60 [2],[10]   66 [1],[5]
Investment, Identifier [Axis]: Juvare, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[16]     10,221 10,221    
Investments, at fair value, ending balance [1],[6],[16]           10,221
Investment, Identifier [Axis]: Juvare, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     2,359 2,359    
Investments, at fair value, ending balance [1],[5],[17]           2,359
Investment, Identifier [Axis]: Juvare, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     745 745    
Investments, at fair value, ending balance [1],[5]           745
Investment, Identifier [Axis]: Juvare, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     98 98    
Investments, at fair value, ending balance [1],[5]           98
Investment, Identifier [Axis]: Kaseya Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     267 267    
Investments, at fair value, ending balance 285 [2],[10]     285 [2],[10]   267 [1],[5]
Investment, Identifier [Axis]: Kaseya Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[19]     23,506 23,506    
Investments, at fair value, ending balance [1],[5],[9],[14],[19]           23,506
Investment, Identifier [Axis]: Kaseya Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     271 271    
Investments, at fair value, ending balance [1],[5]           271
Investment, Identifier [Axis]: Kaseya Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     136 136    
Investments, at fair value, ending balance [1],[5],[14]           136
Investment, Identifier [Axis]: Kaseya Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     86 86    
Investments, at fair value, ending balance [1],[5]           86
Investment, Identifier [Axis]: Kaseya Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     5,787 5,787    
Investments, at fair value, ending balance [1],[5],[26]           5,787
Investment, Identifier [Axis]: Kaseya Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 4,030     4,030    
Investment, Identifier [Axis]: Kentik Technologies, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,578 1,578    
Investments, at fair value, ending balance 2,954 [2],[10]     2,954 [2],[10]   1,578 [1],[5]
Investment, Identifier [Axis]: Kentik Technologies, Inc., Second lien 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 55     55    
Investment, Identifier [Axis]: Kentik Technologies, Inc., Second lien 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: Kentik Technologies, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3     3    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,531     3,531    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,032     3,032    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,858     2,858    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,853     2,853    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,023     2,023    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 614     614    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,543     2,543    
Investment, Identifier [Axis]: Keystone Agency Partners LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,558 3,558    
Investments, at fair value, ending balance [1],[5],[9]           3,558
Investment, Identifier [Axis]: Keystone Agency Partners LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,039 2,039    
Investments, at fair value, ending balance [1],[5]           2,039
Investment, Identifier [Axis]: Keystone Agency Partners LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     2,875 2,875    
Investments, at fair value, ending balance [1],[5],[17]           2,875
Investment, Identifier [Axis]: Keystone Agency Partners LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     618 618    
Investments, at fair value, ending balance [1],[5],[9]           618
Investment, Identifier [Axis]: Keystone Agency Partners LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,108 2,108    
Investments, at fair value, ending balance [1],[5]           2,108
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,087 4,087    
Investments, at fair value, ending balance [1],[5],[9]           4,087
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     120 120    
Investments, at fair value, ending balance [1],[5]           120
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 4,056     4,056    
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Kleinfelder Intermediate, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 440     440    
Investment, Identifier [Axis]: Klick Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[17]     13,629 13,629    
Investments, at fair value, ending balance 13,523 [2],[10],[11],[25],[28]     13,523 [2],[10],[11],[25],[28]   13,629 [1],[5],[7],[8],[17]
Investment, Identifier [Axis]: Klick Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[12]     0 0    
Investments, at fair value, ending balance 3,163 [2],[10],[25],[28]     3,163 [2],[10],[25],[28]   0 [1],[5],[7],[8],[12]
Investment, Identifier [Axis]: Klick Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8]     3,179 3,179    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[28]     0 [2],[10],[13],[25],[28]   3,179 [1],[5],[7],[8]
Investment, Identifier [Axis]: Kodiak Cakes, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     842 842    
Investments, at fair value, ending balance 1,806 [2],[10]     1,806 [2],[10]   842 [1],[5],[26]
Investment, Identifier [Axis]: Kodiak Cakes, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     46,378 46,378    
Investments, at fair value, ending balance 46,028 [2],[10],[11],[20]     46,028 [2],[10],[11],[20]   46,378 [1],[5],[19]
Investment, Identifier [Axis]: Kodiak Cakes, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     15,674 15,674    
Investments, at fair value, ending balance 15,674 [2],[10]     15,674 [2],[10]   15,674 [1],[5]
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (19) (19)    
Investments, at fair value, ending balance (9) [2],[10],[13]     (9) [2],[10],[13]   (19) [1],[5],[12]
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 920 [2],[10]     920 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (23) (23)    
Investments, at fair value, ending balance 259 [2],[10]     259 [2],[10]   (23) [1],[5],[12]
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (3)     (3)    
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (2)     (2)    
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Kona Buyer, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (17)     (17)    
Investment, Identifier [Axis]: Krayden Holdings, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     9,741 9,741    
Investments, at fair value, ending balance 9,766 [2],[10]     9,766 [2],[10]   9,741 [1],[5]
Investment, Identifier [Axis]: Krayden Holdings, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (34) (34)    
Investments, at fair value, ending balance 48 [2],[10]     48 [2],[10]   (34) [1],[5],[12]
Investment, Identifier [Axis]: Krayden Holdings, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (49) (49)    
Investments, at fair value, ending balance 1,954 [2],[10]     1,954 [2],[10]   (49) [1],[5],[12]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     621 621    
Investments, at fair value, ending balance 636 [2],[10]     636 [2],[10]   621 [1],[5]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     671 671    
Investments, at fair value, ending balance 666 [2],[10]     666 [2],[10]   671 [1],[5]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     2,599 2,599    
Investments, at fair value, ending balance 2,579 [2],[10],[11]     2,579 [2],[10],[11]   2,599 [1],[5],[16]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     2,386 2,386    
Investments, at fair value, ending balance 2,368 [2],[10],[11]     2,368 [2],[10],[11]   2,386 [1],[5],[16]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     1,526 1,526    
Investments, at fair value, ending balance 1,513 [2],[11]     1,513 [2],[11]   1,526 [1],[5],[16]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,395 1,395    
Investments, at fair value, ending balance 1,387 [2],[10],[11]     1,387 [2],[10],[11]   1,395 [1],[5]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     615 615    
Investments, at fair value, ending balance 610 [2],[10]     610 [2],[10]   615 [1],[5],[9]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 90 [2],[10]     90 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Krueger-Gilbert Health Physics, LLC, Senior secured 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     90 90    
Investments, at fair value, ending balance 299 [2],[10]     299 [2],[10]   90 [1],[5]
Investment, Identifier [Axis]: LDS Intermediate Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 7,427     7,427    
Investment, Identifier [Axis]: LDS Intermediate Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: LDS Intermediate Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: LMP TR Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     1,691 1,691    
Investments, at fair value, ending balance 622 [2],[10]     622 [2],[10]   1,691 [1]
Investment, Identifier [Axis]: LOV Acquisition LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 25,123     25,123    
Investment, Identifier [Axis]: LOV Acquisition LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Lacker Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     634 634    
Investments, at fair value, ending balance 644 [2],[10],[25],[31],[32]     644 [2],[10],[25],[31],[32]   634 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Lacker Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     142 142    
Investments, at fair value, ending balance 532 [2],[10],[25],[31],[32]     532 [2],[10],[25],[31],[32]   142 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Lacker Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     0 0    
Investments, at fair value, ending balance (1) [2],[10],[13],[25],[31],[32]     (1) [2],[10],[13],[25],[31],[32]   0 [1],[5],[8],[12],[29],[30]
Investment, Identifier [Axis]: LeadsOnline, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     13,049 13,049    
Investments, at fair value, ending balance 12,950 [2],[10],[20]     12,950 [2],[10],[20]   13,049 [1],[5],[19]
Investment, Identifier [Axis]: LeadsOnline, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,303 2,303    
Investments, at fair value, ending balance 2,286 [2],[10]     2,286 [2],[10]   2,303 [1],[5],[9]
Investment, Identifier [Axis]: LeadsOnline, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     667 667    
Investments, at fair value, ending balance 663 [2],[10]     663 [2],[10]   667 [1],[5],[9]
Investment, Identifier [Axis]: LeadsOnline, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Learn-it Systems, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     3,381 3,381    
Investments, at fair value, ending balance 3,386 [2],[10],[15]     3,386 [2],[10],[15]   3,381 [1],[5],[9],[14]
Investment, Identifier [Axis]: Learn-it Systems, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,991 1,991    
Investments, at fair value, ending balance 1,995 [2],[10],[15]     1,995 [2],[10],[15]   1,991 [1],[5],[14]
Investment, Identifier [Axis]: Learn-it Systems, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     847 847    
Investments, at fair value, ending balance 849 [2],[10],[15]     849 [2],[10],[15]   847 [1],[5],[14]
Investment, Identifier [Axis]: Learn-it Systems, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Lighthouse Bidco GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[45] 20,133     20,133    
Investment, Identifier [Axis]: Lighthouse Bidco GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[45] 0     0    
Investment, Identifier [Axis]: Lighthouse Bidco GMBH, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[45] 0     0    
Investment, Identifier [Axis]: Lightning Finco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     14,802 14,802    
Investments, at fair value, ending balance 14,802 [2],[10],[25],[41]     14,802 [2],[10],[25],[41]   14,802 [1],[5],[8],[29]
Investment, Identifier [Axis]: Lightning Finco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     1,692 1,692    
Investments, at fair value, ending balance 1,789 [2],[10],[25],[32],[41]     1,789 [2],[10],[25],[32],[41]   1,692 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Liminex, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     681 681    
Investments, at fair value, ending balance 486 [2],[10]     486 [2],[10]   681 [1],[5]
Investment, Identifier [Axis]: Liminex, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     35,650 35,650    
Investments, at fair value, ending balance 35,471 [2],[10]     35,471 [2],[10]   35,650 [1],[5],[9]
Investment, Identifier [Axis]: Liminex, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     23,516 23,516    
Investments, at fair value, ending balance 23,399 [2],[10]     23,399 [2],[10]   23,516 [1],[5],[9]
Investment, Identifier [Axis]: Liminex, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     15,953 15,953    
Investments, at fair value, ending balance 20,219 [2],[10],[20]     20,219 [2],[10],[20]   15,953 [1],[5],[9]
Investment, Identifier [Axis]: Liminex, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     20,321 20,321    
Investments, at fair value, ending balance 15,872 [2],[10]     15,872 [2],[10]   20,321 [1],[5],[9],[19]
Investment, Identifier [Axis]: Litera Bidco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     5,201 5,201    
Investments, at fair value, ending balance 5,162 [2],[11]     5,162 [2],[11]   5,201 [1],[5],[16]
Investment, Identifier [Axis]: Litera Bidco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,060 1,060    
Investments, at fair value, ending balance 2,061 [2],[10]     2,061 [2],[10]   1,060 [1],[5]
Investment, Identifier [Axis]: Litera Bidco, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Litera Bidco, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: LogicMonitor, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 266     266    
Investment, Identifier [Axis]: LogicMonitor, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 53,749     53,749    
Investment, Identifier [Axis]: LogicMonitor, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Lotus Topco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5,164 5,164    
Investments, at fair value, ending balance 5,125 [2],[11]     5,125 [2],[11]   5,164 [1],[5]
Investment, Identifier [Axis]: Lotus Topco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Lotus Topco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Louisiana Fish Fry Products, Ltd., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     331 331    
Investments, at fair value, ending balance 253 [2],[10]     253 [2],[10]   331 [1],[5]
Investment, Identifier [Axis]: Louisiana Fish Fry Products, Ltd., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[16]     13,564 13,564    
Investments, at fair value, ending balance 13,458 [2],[10],[11]     13,458 [2],[10],[11]   13,564 [1],[5],[6],[9],[16]
Investment, Identifier [Axis]: Louisiana Fish Fry Products, Ltd., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     192 192    
Investments, at fair value, ending balance 192 [2],[10]     192 [2],[10]   192 [1],[5]
Investment, Identifier [Axis]: Louisiana Fish Fry Products, Ltd., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     36 36    
Investments, at fair value, ending balance 36 [2],[10]     36 [2],[10]   36 [1],[5]
Investment, Identifier [Axis]: MAPF Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[17],[18],[19]     46,258 46,258    
Investments, at fair value, ending balance 49,767 [2],[10],[20]     49,767 [2],[10],[20]   46,258 [1],[5],[6],[16],[17],[18],[19]
Investment, Identifier [Axis]: MAPF Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     534 534    
Investments, at fair value, ending balance 520 [2],[10]     520 [2],[10]   534 [1],[5]
Investment, Identifier [Axis]: MAPF Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,482 1,482    
Investments, at fair value, ending balance 1,595 [2],[10]     1,595 [2],[10]   1,482 [1],[5],[9]
Investment, Identifier [Axis]: MAPF Holdings, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,076 1,076    
Investments, at fair value, ending balance 1,990 [2],[10],[15]     1,990 [2],[10],[15]   1,076 [1],[5]
Investment, Identifier [Axis]: MMan Acquisition Co.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     12,205 12,205 12,790 12,790
Gross additions       362   11,979
Gross reductions       0   (11,344)
Net change in unrealized appreciation (depreciation)       (711)   10,406
Net realized gain (loss)       0   (11,626)
Investments, at fair value, ending balance 11,856     11,856   12,205
Interest, dividend and fee income       377   439
Investment, Identifier [Axis]: MMan Acquisition Co., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,073 1,073    
Investments, at fair value, ending balance [1],[5],[14]           1,073
Investment, Identifier [Axis]: MMan Acquisition Co., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,813 1,813    
Investments, at fair value, ending balance 1,968 [2],[10],[15]     1,968 [2],[10],[15]   1,813 [1],[5],[14]
Investment, Identifier [Axis]: MMan Acquisition Co., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 1,173     1,173    
Investment, Identifier [Axis]: MMan Acquisition Co., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,153 1,153    
Investments, at fair value, ending balance 1,261 [2],[10],[15]     1,261 [2],[10],[15]   1,153 [1],[5],[14]
Investment, Identifier [Axis]: MMan Acquisition Co., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     334 334    
Investments, at fair value, ending balance 365 [2],[10],[15]     365 [2],[10],[15]   334 [1],[5],[14]
Investment, Identifier [Axis]: MMan Acquisition Co., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,832 7,832    
Investments, at fair value, ending balance 7,089 [2],[10]     7,089 [2],[10]   7,832 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     546 546    
Investments, at fair value, ending balance 339 [2],[10]     339 [2],[10]   546 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[18],[19]     32,559 32,559    
Investments, at fair value, ending balance 32,305 [2],[10],[11],[20]     32,305 [2],[10],[11],[20]   32,559 [1],[5],[6],[16],[18],[19]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     396 396    
Investments, at fair value, ending balance 396 [2],[10]     396 [2],[10]   396 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     264 264    
Investments, at fair value, ending balance 263 [2],[10]     263 [2],[10]   264 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     201 201    
Investments, at fair value, ending balance 199 [2],[10]     199 [2],[10]   201 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     88 88    
Investments, at fair value, ending balance 88 [2],[10]     88 [2],[10]   88 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     88 88    
Investments, at fair value, ending balance 88 [2],[10]     88 [2],[10]   88 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     3,827 3,827    
Investments, at fair value, ending balance 3,798 [2],[10]     3,798 [2],[10]   3,827 [1],[5],[17]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     3,581 3,581    
Investments, at fair value, ending balance 3,553 [2],[10],[11]     3,553 [2],[10],[11]   3,581 [1],[5],[16]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     3,502 3,502    
Investments, at fair value, ending balance 3,474 [2],[11],[20]     3,474 [2],[11],[20]   3,502 [1],[5],[19]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     2,594 2,594    
Investments, at fair value, ending balance 2,575 [2],[11],[20]     2,575 [2],[11],[20]   2,594 [1],[5],[19]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     2,140 2,140    
Investments, at fair value, ending balance 2,123 [2],[10]     2,123 [2],[10]   2,140 [1],[5],[17]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     1,973 1,973    
Investments, at fair value, ending balance 1,958 [2],[10]     1,958 [2],[10]   1,973 [1],[5],[17]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     718 718    
Investments, at fair value, ending balance 712 [2],[10]     712 [2],[10]   718 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     528 528    
Investments, at fair value, ending balance 524 [2],[10]     524 [2],[10]   528 [1],[5]
Investment, Identifier [Axis]: MOP GM Holding, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     36 36    
Investments, at fair value, ending balance 60 [2],[10]     60 [2],[10]   36 [1],[5]
Investment, Identifier [Axis]: MRH Trowe Germany GMBH, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[44]     789 789    
Investments, at fair value, ending balance [1],[5],[8],[30],[44]           789
Investment, Identifier [Axis]: MRH Trowe Germany GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[45] (3)     (3)    
Investment, Identifier [Axis]: MRH Trowe Germany GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[45] 6,234     6,234    
Investment, Identifier [Axis]: MRH Trowe Germany GMBH, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[45] (10)     (10)    
Investment, Identifier [Axis]: MRI Software, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[19]     28,625 28,625    
Investments, at fair value, ending balance 32,820 [2],[10],[11],[20]     32,820 [2],[10],[11],[20]   28,625 [1],[5],[6],[16],[19]
Investment, Identifier [Axis]: MRI Software, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17],[19]     13,023 13,023    
Investments, at fair value, ending balance 13,053 [2],[10],[11],[20]     13,053 [2],[10],[11],[20]   13,023 [1],[5],[16],[17],[19]
Investment, Identifier [Axis]: MRI Software, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (31) (31)    
Investments, at fair value, ending balance 176 [2],[10]     176 [2],[10]   (31) [1],[5],[12]
Investment, Identifier [Axis]: MRI Software, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     938 938    
Investments, at fair value, ending balance 7,993 [2],[10]     7,993 [2],[10]   938 [1],[5]
Investment, Identifier [Axis]: MRI Software, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,086 3,086    
Investments, at fair value, ending balance [1],[5]           3,086
Investment, Identifier [Axis]: MWD Management, LLC & MWD Services, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     660 660    
Investments, at fair value, ending balance 624 [2],[10]     624 [2],[10]   660 [1],[5]
Investment, Identifier [Axis]: MYOB Invest Co Pty Ltd, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[48] 35,572     35,572    
Investment, Identifier [Axis]: Majesco, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     324 324    
Investments, at fair value, ending balance 390 [2],[10]     390 [2],[10]   324 [1],[5]
Investment, Identifier [Axis]: Majesco, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16],[19]     28,248 28,248    
Investments, at fair value, ending balance 28,027 [2],[11],[20]     28,027 [2],[11],[20]   28,248 [1],[9],[16],[19]
Investment, Identifier [Axis]: Majesco, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Majesco, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     611 611    
Investments, at fair value, ending balance 653 [2],[10],[27]     653 [2],[10],[27]   611 [1],[5],[26]
Investment, Identifier [Axis]: MakerSights, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     104 104    
Investments, at fair value, ending balance 96 [2],[10]     96 [2],[10]   104 [1],[5]
Investment, Identifier [Axis]: Marcone Yellowstone Buyer Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     17,915 17,915    
Investments, at fair value, ending balance 18,672 [2],[10],[15]     18,672 [2],[10],[15]   17,915 [1],[5],[9]
Investment, Identifier [Axis]: Marcone Yellowstone Buyer Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     18,583 18,583    
Investments, at fair value, ending balance 19,367 [2],[10],[15]     19,367 [2],[10],[15]   18,583 [1],[5],[9],[17]
Investment, Identifier [Axis]: Marcone Yellowstone Buyer Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,563 5,563    
Investments, at fair value, ending balance 5,780 [2],[10],[15]     5,780 [2],[10],[15]   5,563 [1],[5],[9]
Investment, Identifier [Axis]: Marcone Yellowstone Buyer Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,274 2,274    
Investments, at fair value, ending balance 2,370 [2],[10],[15]     2,370 [2],[10],[15]   2,274 [1],[5],[9]
Investment, Identifier [Axis]: Marcone Yellowstone Buyer Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     5,953 5,953    
Investments, at fair value, ending balance 6,204 [2],[10],[15]     6,204 [2],[10],[15]   5,953 [1],[5],[17]
Investment, Identifier [Axis]: Mario Purchaser, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     410 410    
Investments, at fair value, ending balance 10,844 [2],[10],[11]     10,844 [2],[10],[11]   410 [1],[5]
Investment, Identifier [Axis]: Mario Purchaser, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     11,270 11,270    
Investments, at fair value, ending balance 4,993 [2],[10]     4,993 [2],[10]   11,270 [1],[5],[9]
Investment, Identifier [Axis]: Mario Purchaser, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     4,384 4,384    
Investments, at fair value, ending balance 4,871 [2],[10],[15]     4,871 [2],[10],[15]   4,384 [1],[5],[14]
Investment, Identifier [Axis]: Mario Purchaser, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5,188 5,188    
Investments, at fair value, ending balance 435 [2],[10]     435 [2],[10]   5,188 [1],[5]
Investment, Identifier [Axis]: Mario Purchaser, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     14 14    
Investments, at fair value, ending balance 20 [2],[10]     20 [2],[10]   14 [1],[5]
Investment, Identifier [Axis]: Massage Envy, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,682 1,682    
Investments, at fair value, ending balance 1,947 [2],[10]     1,947 [2],[10]   1,682 [1],[5]
Investment, Identifier [Axis]: Matrix42 Holding GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[23],[30]     10,121 10,121    
Investments, at fair value, ending balance 10,709 [2],[10],[25],[32],[45]     10,709 [2],[10],[25],[32],[45]   10,121 [1],[5],[8],[9],[23],[30]
Investment, Identifier [Axis]: Matrix42 Holding GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[23],[30]     1,533 1,533    
Investments, at fair value, ending balance 1,622 [2],[10],[25],[32],[45]     1,622 [2],[10],[25],[32],[45]   1,533 [1],[5],[8],[9],[23],[30]
Investment, Identifier [Axis]: Matrix42 Holding GMBH, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[23],[30]     789 789    
Investments, at fair value, ending balance 835 [2],[10],[25],[32],[45]     835 [2],[10],[25],[32],[45]   789 [1],[5],[8],[9],[23],[30]
Investment, Identifier [Axis]: Matrix42 Holding GMBH, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[23],[30]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[32],[45]     0 [2],[10],[13],[25],[32],[45]   0 [1],[5],[8],[12],[23],[30]
Investment, Identifier [Axis]: Matrix42 Holding GMBH, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[23]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[45]     0 [2],[10],[25],[45]   0 [1],[5],[8],[23]
Investment, Identifier [Axis]: Medlar Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[49] 27,047     27,047    
Investment, Identifier [Axis]: Medlar Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[49] 33,078     33,078    
Investment, Identifier [Axis]: Medlar Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[49] 0     0    
Investment, Identifier [Axis]: Mendocino Farms, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,433 1,433    
Investments, at fair value, ending balance 1,370 [2],[10]     1,370 [2],[10]   1,433 [1],[5],[26]
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 983     983    
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,001 1,001    
Investments, at fair value, ending balance [1],[5],[9]           1,001
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   0 [1],[5]
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     112 112    
Investments, at fair value, ending balance 109 [2],[10]     109 [2],[10]   112 [1],[5]
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 110     110    
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (86)     (86)    
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 56     56    
Investment, Identifier [Axis]: Mendocino Farms, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 56     56    
Investment, Identifier [Axis]: Menlo Ridgeview Co-Invest, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 946     946    
Investment, Identifier [Axis]: Messenger, LLC, LLC units 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     620 620    
Investments, at fair value, ending balance 816 [2],[10]     816 [2],[10]   620 [1],[5]
Investment, Identifier [Axis]: Messenger, LLC, LLC units 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Messenger, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[18]     14,397 14,397    
Investments, at fair value, ending balance 14,397 [2],[10],[11]     14,397 [2],[10],[11]   14,397 [1],[5],[9],[16],[18]
Investment, Identifier [Axis]: Messenger, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30]     926 926    
Investments, at fair value, ending balance 950 [2],[10],[25],[32]     950 [2],[10],[25],[32]   926 [1],[5],[8],[30]
Investment, Identifier [Axis]: Messenger, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 520     520    
Investment, Identifier [Axis]: Messenger, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[32]     0 [2],[10],[25],[32]   0 [1],[5],[8],[30]
Investment, Identifier [Axis]: Messenger, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     1,508 1,508    
Investments, at fair value, ending balance 1,508 [2],[10],[11]     1,508 [2],[10],[11]   1,508 [1],[5],[16]
Investment, Identifier [Axis]: Messenger, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     756 756    
Investments, at fair value, ending balance 756 [2],[10]     756 [2],[10]   756 [1],[5],[9]
Investment, Identifier [Axis]: Messenger, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Messenger, LLC, One stop3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     520 520    
Investments, at fair value, ending balance [1],[5]           520
Investment, Identifier [Axis]: Metal Supermarkets US Buyer, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 0     0    
Investment, Identifier [Axis]: Metal Supermarkets US Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 11,544     11,544    
Investment, Identifier [Axis]: Metal Supermarkets US Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[28] 0     0    
Investment, Identifier [Axis]: Metal Supermarkets US Buyer, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 347     347    
Investment, Identifier [Axis]: Metatiedot Bidco Oy & Metatiedot US, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[50] 17,332     17,332    
Investment, Identifier [Axis]: Metatiedot Bidco Oy & Metatiedot US, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[50] 11,017     11,017    
Investment, Identifier [Axis]: Metatiedot Bidco Oy & Metatiedot US, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[50] 140     140    
Investment, Identifier [Axis]: Metatiedot Bidco Oy & Metatiedot US, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[50] 0     0    
Investment, Identifier [Axis]: Midwest Veterinary Partners, LLC, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     2,123 2,123    
Investments, at fair value, ending balance [1],[5],[26]           2,123
Investment, Identifier [Axis]: Midwest Veterinary Partners, LLC, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     68 68    
Investments, at fair value, ending balance [1],[5],[26]           68
Investment, Identifier [Axis]: Midwest Veterinary Partners, LLC, Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     482 482    
Investments, at fair value, ending balance [1],[5]           482
Investment, Identifier [Axis]: Mindbody, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     61,966 61,966    
Investments, at fair value, ending balance 61,966 [2],[10]     61,966 [2],[10]   61,966 [1],[5],[9]
Investment, Identifier [Axis]: Mindbody, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,134 2,134    
Investments, at fair value, ending balance 2,134 [2],[10]     2,134 [2],[10]   2,134 [1],[5],[9]
Investment, Identifier [Axis]: Mindbody, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Ministry Brands Holdings LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     704 704    
Investments, at fair value, ending balance 620 [2],[10]     620 [2],[10]   704 [1],[5]
Investment, Identifier [Axis]: Ministry Brands Holdings LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     30,448 30,448    
Investments, at fair value, ending balance 30,214 [2],[10]     30,214 [2],[10]   30,448 [1],[5],[9]
Investment, Identifier [Axis]: Ministry Brands Holdings LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,864 2,864    
Investments, at fair value, ending balance 2,843 [2],[10]     2,843 [2],[10]   2,864 [1],[5]
Investment, Identifier [Axis]: Ministry Brands Holdings LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (6) (6)    
Investments, at fair value, ending balance 24 [2],[10]     24 [2],[10]   (6) [1],[5],[12]
Investment, Identifier [Axis]: Modernizing Medicine, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 31,838     31,838    
Investment, Identifier [Axis]: Modernizing Medicine, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (30)     (30)    
Investment, Identifier [Axis]: Modernizing Medicine, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 4,432     4,432    
Investment, Identifier [Axis]: Movement Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     136 136    
Investments, at fair value, ending balance 108 [2],[10],[25],[31]     108 [2],[10],[25],[31]   136 [1],[5]
Investment, Identifier [Axis]: Movement Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     841 841    
Investments, at fair value, ending balance 834 [2],[10],[25],[31]     834 [2],[10],[25],[31]   841 [1],[5],[9]
Investment, Identifier [Axis]: Movement Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[31]     0 [2],[10],[25],[31]   0 [1],[5]
Investment, Identifier [Axis]: Movement Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[31]     0 [2],[10],[13],[25],[31]   0 [1],[5],[12]
Investment, Identifier [Axis]: NBG Acquisition Corp. and NBG-P Acquisition Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16],[17],[18],[19]     33,004 33,004    
Investments, at fair value, ending balance 31,737 [2],[10],[11],[20]     31,737 [2],[10],[11],[20]   33,004 [1],[9],[16],[17],[18],[19]
Investment, Identifier [Axis]: NBG Acquisition Corp. and NBG-P Acquisition Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     767 767    
Investments, at fair value, ending balance 738 [2],[10]     738 [2],[10]   767 [1],[5]
Investment, Identifier [Axis]: NBG Acquisition Corp. and NBG-P Acquisition Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     292 292    
Investments, at fair value, ending balance 438 [2],[10]     438 [2],[10]   292 [1],[5]
Investment, Identifier [Axis]: NDX Parent, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     11 11    
Investments, at fair value, ending balance [1],[5]           11
Investment, Identifier [Axis]: NDX Parent, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     82 82    
Investments, at fair value, ending balance [1],[5]           82
Investment, Identifier [Axis]: NSG Buyer, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     3,616 3,616    
Investments, at fair value, ending balance 3,892 [2],[10],[25]     3,892 [2],[10],[25]   3,616 [1],[5],[8]
Investment, Identifier [Axis]: NSG Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[17],[18]     34,589 34,589    
Investments, at fair value, ending balance 37,055 [2],[10],[11]     37,055 [2],[10],[11]   34,589 [1],[5],[6],[17],[18]
Investment, Identifier [Axis]: NSG Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 145 [2],[10]     145 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: NSG Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: NSG Buyer, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,785 1,785    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   1,785 [1],[5]
Investment, Identifier [Axis]: NTI Connect, LLC, Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,529 1,529    
Investments, at fair value, ending balance 1,529 [2],[10],[11]     1,529 [2],[10],[11]   1,529 [1],[5],[9]
Investment, Identifier [Axis]: National Express Wash Parent Holdco, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     134 134    
Investments, at fair value, ending balance 176 [2],[10]     176 [2],[10]   134 [1],[5]
Investment, Identifier [Axis]: National Express Wash Parent Holdco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     9,428 9,428    
Investments, at fair value, ending balance 13,314 [2],[10]     13,314 [2],[10]   9,428 [1],[5],[17]
Investment, Identifier [Axis]: National Express Wash Parent Holdco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     132 132    
Investments, at fair value, ending balance 1,449 [2],[10]     1,449 [2],[10]   132 [1],[5]
Investment, Identifier [Axis]: National Express Wash Parent Holdco, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,283 [2],[10]     1,283 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: National Express Wash Parent Holdco, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Navex TopCo, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,382 5,382    
Investments, at fair value, ending balance 5,342 [2],[10]     5,342 [2],[10]   5,382 [1],[5],[9]
Investment, Identifier [Axis]: Navex TopCo, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Naviga Inc., Senior secured            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[21]     48 48    
Investments, at fair value, ending balance 67 [2],[10],[15],[22]     67 [2],[10],[15],[22]   48 [1],[5],[21]
Investment, Identifier [Axis]: Neptune Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     16,180 16,180    
Investments, at fair value, ending balance 16,058 [2],[11]     16,058 [2],[11]   16,180 [1],[5],[16]
Investment, Identifier [Axis]: Neptune Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Net Health Acquisition Corp., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,311 2,311    
Investments, at fair value, ending balance 2,392 [2],[10]     2,392 [2],[10]   2,311 [1],[5]
Investment, Identifier [Axis]: Netsmart Technologies, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     50,812 50,812    
Investments, at fair value, ending balance 52,341 [2],[10],[15]     52,341 [2],[10],[15]   50,812 [1],[5],[14]
Investment, Identifier [Axis]: Netsmart Technologies, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (70) (70)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (70) [1],[5],[12]
Investment, Identifier [Axis]: Netsmart Technologies, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (34) (34)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (34) [1],[5],[12]
Investment, Identifier [Axis]: Netwrix Corporation, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     18 18    
Investments, at fair value, ending balance 20 [2],[10]     20 [2],[10]   18 [1],[5]
Investment, Identifier [Axis]: Netwrix Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[17]     7,975 7,975    
Investments, at fair value, ending balance 7,915 [2],[10],[11]     7,915 [2],[10],[11]   7,975 [1],[5],[6],[17]
Investment, Identifier [Axis]: Netwrix Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 384 [2],[10]     384 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Netwrix Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     422 422    
Investments, at fair value, ending balance 90 [2],[10]     90 [2],[10]   422 [1],[5]
Investment, Identifier [Axis]: Netwrix Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     311 311    
Investments, at fair value, ending balance [1],[5],[7],[8],[30]           311
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[14],[30]     25,165 25,165    
Investments, at fair value, ending balance [1],[5],[7],[8],[9],[14],[30]           25,165
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[7],[8],[9],[18]     5,646 5,646    
Investments, at fair value, ending balance [1],[7],[8],[9],[18]           5,646
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[18]     3,984 3,984    
Investments, at fair value, ending balance [1],[5],[7],[8],[9],[18]           3,984
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     1,576 1,576    
Investments, at fair value, ending balance [1],[5],[7],[8],[30]           1,576
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     821 821    
Investments, at fair value, ending balance [1],[5],[7],[8],[30]           821
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[14]     125 125    
Investments, at fair value, ending balance [1],[5],[7],[8],[14]           125
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     65 65    
Investments, at fair value, ending balance [1],[5],[7],[8],[30]           65
Investment, Identifier [Axis]: New Look (Delaware) Corporation and NL1 AcquireCo, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[12]     (4) (4)    
Investments, at fair value, ending balance [1],[5],[7],[8],[12]           (4)
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 446     446    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[28],[32] 26,128     26,128    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11],[25],[28] 5,836     5,836    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11],[25],[28] 4,118     4,118    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 1,619     1,619    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 843     843    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 174     174    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[28] 131     131    
Investment, Identifier [Axis]: New Look Corporation and New Look Vision Group Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[28] 0     0    
Investment, Identifier [Axis]: North Haven Falcon Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     7,285 7,285    
Investments, at fair value, ending balance 4,920 [2],[10],[15],[22]     4,920 [2],[10],[15],[22]   7,285 [1],[5],[9],[14]
Investment, Identifier [Axis]: North Haven Falcon Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,220 1,220    
Investments, at fair value, ending balance 822 [2],[10],[15],[22]     822 [2],[10],[15],[22]   1,220 [1],[5],[14]
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1]     846 846    
Investments, at fair value, ending balance 1,232 [2]     1,232 [2]   846 [1]
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 157     157    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11] 1,352     1,352    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 199     199    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 99     99    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 673     673    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 2,258     2,258    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 479     479    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 901     901    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 17            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 682     682    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 18            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 756     756    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 19            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 23     23    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 1,548     1,548    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 20            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 331     331    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 21            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,334     1,334    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 22            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 101     101    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,364     1,364    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 281     281    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 12,160     12,160    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 1,466     1,466    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,404     1,404    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11] 4,097     4,097    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,357     1,357    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Second lien 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,529 [2],[10],[15]     1,529 [2],[10],[15]   0 [1],[5],[12]
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Second lien 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     2,290 2,290    
Investments, at fair value, ending balance (7) [2],[10],[13]     (7) [2],[10],[13]   2,290 [1],[5],[14]
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Second lien 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,511 1,511    
Investments, at fair value, ending balance 2,322 [2],[10],[15]     2,322 [2],[10],[15]   1,511 [1],[5],[14]
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Second lien 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 385     385    
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,568 1,568    
Investments, at fair value, ending balance [1],[5]           1,568
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     201 201    
Investments, at fair value, ending balance [1],[5]           201
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     100 100    
Investments, at fair value, ending balance [1],[5]           100
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     166 166    
Investments, at fair value, ending balance [1],[5]           166
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,287 2,287    
Investments, at fair value, ending balance [1],[5]           2,287
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     485 485    
Investments, at fair value, ending balance [1],[5]           485
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     910 910    
Investments, at fair value, ending balance [1],[5]           910
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     689 689    
Investments, at fair value, ending balance [1],[5]           689
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     158 158    
Investments, at fair value, ending balance [1],[5]           158
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     285 285    
Investments, at fair value, ending balance [1],[5]           285
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[9],[16],[18]     12,315 12,315    
Investments, at fair value, ending balance [1],[6],[9],[16],[18]           12,315
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,485 1,485    
Investments, at fair value, ending balance [1],[5]           1,485
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,422 1,422    
Investments, at fair value, ending balance [1],[5]           1,422
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     4,149 4,149    
Investments, at fair value, ending balance [1],[16],[18]           4,149
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,374 1,374    
Investments, at fair value, ending balance [1],[5]           1,374
Investment, Identifier [Axis]: North Haven Stack Buyer, LLC, Senior secured 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[16],[18]     1,369 1,369    
Investments, at fair value, ending balance [1],[16],[18]           1,369
Investment, Identifier [Axis]: Norvax, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[19]     38,860 38,860    
Investments, at fair value, ending balance [1],[5],[8],[9],[19]           38,860
Investment, Identifier [Axis]: Norvax, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9]     12,026 12,026    
Investments, at fair value, ending balance [1],[5],[8],[9]           12,026
Investment, Identifier [Axis]: OEConnection, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     10,288 10,288    
Investments, at fair value, ending balance 10,211 [2],[11]     10,211 [2],[11]   10,288 [1],[5],[16]
Investment, Identifier [Axis]: OEConnection, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: OEConnection, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 1,782 [2],[10]     1,782 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: OEConnection, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,745 1,745    
Investments, at fair value, ending balance [1],[5],[9]           1,745
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     331 331    
Investments, at fair value, ending balance [1],[5]           331
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,723     1,723    
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 760     760    
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 50     50    
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (5)     (5)    
Investment, Identifier [Axis]: Oakbridge Insurance Agency LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     412 412    
Investments, at fair value, ending balance 517 [2],[10]     517 [2],[10]   412 [1],[5]
Investment, Identifier [Axis]: Oakbridge Insurance Agency LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,281 2,281    
Investments, at fair value, ending balance 2,270 [2],[10]     2,270 [2],[10]   2,281 [1],[5],[9]
Investment, Identifier [Axis]: Oakbridge Insurance Agency LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     30 30    
Investments, at fair value, ending balance 944 [2],[10]     944 [2],[10]   30 [1],[5]
Investment, Identifier [Axis]: Oakbridge Insurance Agency LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     91 91    
Investments, at fair value, ending balance 7 [2],[10]     7 [2],[10]   91 [1],[5]
Investment, Identifier [Axis]: Oakbridge Insurance Agency LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (10)     (10)    
Investment, Identifier [Axis]: Onapsis, Inc., Virtual Forge GMBH and Onapsis GMBH, Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     20 20    
Investments, at fair value, ending balance 16 [2],[10]     16 [2],[10]   20 [1],[5]
Investment, Identifier [Axis]: Onit, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 5,415     5,415    
Investment, Identifier [Axis]: Onit, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Onit, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Onit, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     128 128    
Investments, at fair value, ending balance [1],[5],[26]           128
Investment, Identifier [Axis]: Onit, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     20 20    
Investments, at fair value, ending balance 16 [2],[10]     16 [2],[10]   20 [1],[5]
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     24,936 24,936 24,438 24,438
Gross additions       12,072   27,853
Gross reductions       (8,225)   (23,040)
Net change in unrealized appreciation (depreciation)       (4,958)   (4,272)
Net realized gain (loss)       0   (43)
Investments, at fair value, ending balance 23,825     23,825   24,936
Interest, dividend and fee income       182   629
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,764 3,764    
Investments, at fair value, ending balance 245 [2],[10]     245 [2],[10]   3,764 [1],[5]
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 3,847     3,847    
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Opening Day Borrower 111 LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     21,172 21,172    
Investments, at fair value, ending balance 19,733 [2],[10]     19,733 [2],[10]   21,172 [1],[5]
Investment, Identifier [Axis]: Optimizely North America, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,528 1,528    
Investments, at fair value, ending balance 1,667 [2],[10]     1,667 [2],[10]   1,528 [1],[5]
Investment, Identifier [Axis]: Optimizely North America, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[18],[19]     25,860 25,860    
Investments, at fair value, ending balance 38,224 [2],[10]     38,224 [2],[10]   25,860 [1],[9],[18],[19]
Investment, Identifier [Axis]: Optimizely North America, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30]     23,933 23,933    
Investments, at fair value, ending balance 15,943 [2],[10],[25],[32]     15,943 [2],[10],[25],[32]   23,933 [1],[5],[8],[30]
Investment, Identifier [Axis]: Optimizely North America, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[18],[19]     14,317 14,317    
Investments, at fair value, ending balance 6,121 [2],[10],[25],[32]     6,121 [2],[10],[25],[32]   14,317 [1],[6],[18],[19]
Investment, Identifier [Axis]: Optimizely North America, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[9]     7,956 7,956    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   7,956 [1],[6],[9]
Investment, Identifier [Axis]: Optimizely North America, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Orsay Bidco 1 B.V. and Sky Group Holding B.V., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[33]     0 0    
Investments, at fair value, ending balance [1],[5],[8],[12],[30],[33]           0
Investment, Identifier [Axis]: Orsay Bidco 1 B.V. and Sky Group Holding B.V., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[34] 2,342     2,342    
Investment, Identifier [Axis]: Orsay Bidco 1 B.V. and Sky Group Holding B.V., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32],[34] 348     348    
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     238 238    
Investments, at fair value, ending balance 342 [2],[10]     342 [2],[10]   238 [1],[5]
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[17]     24,068 24,068    
Investments, at fair value, ending balance 13,039 [2],[10],[11]     13,039 [2],[10],[11]   24,068 [1],[5],[6],[16],[17]
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (6) (6)    
Investments, at fair value, ending balance (8) [2],[10],[13]     (8) [2],[10],[13]   (6) [1],[5],[12]
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32] 12,105     12,105    
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (31)     (31)    
Investment, Identifier [Axis]: P&P Food Safety Holdings, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     35 35    
Investments, at fair value, ending balance 41 [2],[10]     41 [2],[10]   35 [1],[5]
Investment, Identifier [Axis]: PADI Holdco, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     868 868    
Investments, at fair value, ending balance 1,398 [2],[10],[27]     1,398 [2],[10],[27]   868 [1],[5]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[6],[18]     21,353 21,353    
Investments, at fair value, ending balance 21,189 [2],[11]     21,189 [2],[11]   21,353 [1],[6],[18]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30]     20,130 20,130    
Investments, at fair value, ending balance 21,132 [2],[10],[25],[32]     21,132 [2],[10],[25],[32]   20,130 [1],[5],[8],[30]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     823 823    
Investments, at fair value, ending balance 7,479 [2],[10],[25],[32]     7,479 [2],[10],[25],[32]   823 [1],[5]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     170 170    
Investments, at fair value, ending balance 816 [2],[10]     816 [2],[10]   170 [1],[5]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     214 214    
Investments, at fair value, ending balance 1,000 [2],[10]     1,000 [2],[10]   214 [1],[5]
Investment, Identifier [Axis]: PADI Holdco, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 169     169    
Investment, Identifier [Axis]: PAS Parent Inc. One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[16],[17],[18]     54,960 54,960    
Investments, at fair value, ending balance [1],[5],[6],[9],[16],[17],[18]           54,960
Investment, Identifier [Axis]: PAS Parent Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,618 1,618    
Investments, at fair value, ending balance 1,875 [2],[10]     1,875 [2],[10]   1,618 [1],[5]
Investment, Identifier [Axis]: PAS Parent Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (39) (39)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (39) [1],[5],[12]
Investment, Identifier [Axis]: PAS Parent Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 55,096     55,096    
Investment, Identifier [Axis]: PAS Parent Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     124 124    
Investments, at fair value, ending balance 55 [2],[10]     55 [2],[10]   124 [1],[5]
Investment, Identifier [Axis]: PAS Parent Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,608 2,608    
Investments, at fair value, ending balance 2,986 [2],[10]     2,986 [2],[10]   2,608 [1],[5]
Investment, Identifier [Axis]: PAS Parent Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     299 299    
Investments, at fair value, ending balance 339 [2],[10]     339 [2],[10]   299 [1],[5]
Investment, Identifier [Axis]: PB Group Holdings, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     886 886    
Investments, at fair value, ending balance 1,054 [2],[10]     1,054 [2],[10]   886 [1],[5]
Investment, Identifier [Axis]: PB Group Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     36,544 36,544    
Investments, at fair value, ending balance 37,409 [2],[10],[15]     37,409 [2],[10],[15]   36,544 [1],[5],[14]
Investment, Identifier [Axis]: PB Group Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (22) (22)    
Investments, at fair value, ending balance 513 [2],[10]     513 [2],[10]   (22) [1],[5],[12]
Investment, Identifier [Axis]: PDI TA Holdings, Inc, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5,660 5,660    
Investments, at fair value, ending balance [1],[5]           5,660
Investment, Identifier [Axis]: PDI TA Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,143 1,143    
Investments, at fair value, ending balance 11,464 [2],[10]     11,464 [2],[10]   1,143 [1],[5],[9]
Investment, Identifier [Axis]: PDI TA Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 35 [2],[10]     35 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: PDI TA Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 117 [2],[10]     117 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: PDI TA Holdings, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 6,305     6,305    
Investment, Identifier [Axis]: PDQ Intermediate, Inc., Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     114 114    
Investments, at fair value, ending balance 126 [2],[10],[15]     126 [2],[10],[15]   114 [1],[5],[14]
Investment, Identifier [Axis]: PHM NL SP Bidco B.V., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[33]     46,023 46,023    
Investments, at fair value, ending balance 52,141 [2],[10],[15],[25],[31],[32]     52,141 [2],[10],[15],[25],[31],[32]   46,023 [1],[5],[8],[14],[30],[33]
Investment, Identifier [Axis]: PHM NL SP Bidco B.V., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[33]     17,994 17,994    
Investments, at fair value, ending balance 19,281 [2],[10],[15],[25],[31]     19,281 [2],[10],[15],[25],[31]   17,994 [1],[5],[8],[14],[33]
Investment, Identifier [Axis]: PHM NL SP Bidco B.V., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[33]     10,348 10,348    
Investments, at fair value, ending balance 11,552 [2],[10],[15],[25],[31],[32]     11,552 [2],[10],[15],[25],[31],[32]   10,348 [1],[5],[8],[14],[30],[33]
Investment, Identifier [Axis]: PHM NL SP Bidco B.V., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[33]     4,807 4,807    
Investments, at fair value, ending balance 5,529 [2],[10],[15],[25],[31],[32]     5,529 [2],[10],[15],[25],[31],[32]   4,807 [1],[5],[8],[14],[30],[33]
Investment, Identifier [Axis]: PING Identity Holding Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     15,145 15,145    
Investments, at fair value, ending balance 15,031 [2],[10]     15,031 [2],[10]   15,145 [1],[5],[9]
Investment, Identifier [Axis]: PING Identity Holding Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: POY Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     966 966    
Investments, at fair value, ending balance 635 [2],[10]     635 [2],[10]   966 [1],[5]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17],[18],[19]     28,489 28,489    
Investments, at fair value, ending balance 27,986 [2],[10],[11],[20]     27,986 [2],[10],[11],[20]   28,489 [1],[5],[9],[17],[18],[19]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,703 3,703    
Investments, at fair value, ending balance 3,639 [2],[10],[11]     3,639 [2],[10],[11]   3,703 [1],[5],[9]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     1,311 1,311    
Investments, at fair value, ending balance 1,288 [2],[10],[11]     1,288 [2],[10],[11]   1,311 [1],[5],[16]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     873 873    
Investments, at fair value, ending balance 858 [2],[10]     858 [2],[10]   873 [1],[5]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     651 651    
Investments, at fair value, ending balance 640 [2],[10]     640 [2],[10]   651 [1],[5]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     291 291    
Investments, at fair value, ending balance 286 [2],[10]     286 [2],[10]   291 [1],[5]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     31 31    
Investments, at fair value, ending balance (4) [2],[10],[13]     (4) [2],[10],[13]   31 [1],[5]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (33) [2],[10],[13]     (33) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: POY Holdings, LLC, One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,244     2,244    
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16],[18]     14,189 14,189    
Investments, at fair value, ending balance 14,082 [2],[10],[11]     14,082 [2],[10],[11]   14,189 [1],[5],[9],[16],[18]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     9,108 9,108    
Investments, at fair value, ending balance 10,140 [2],[10],[15]     10,140 [2],[10],[15]   9,108 [1],[5],[14]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,799 1,799    
Investments, at fair value, ending balance 5,501 [2],[10]     5,501 [2],[10]   1,799 [1],[5],[14]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     416 416    
Investments, at fair value, ending balance 1,993 [2],[10],[15]     1,993 [2],[10],[15]   416 [1],[5],[14]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     76 76    
Investments, at fair value, ending balance 461 [2],[10],[15]     461 [2],[10],[15]   76 [1],[5],[14]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     75 75    
Investments, at fair value, ending balance 83 [2],[10],[15]     83 [2],[10],[15]   75 [1],[5],[14]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 84 [2],[10],[15]     84 [2],[10],[15]   0 [1],[5],[12]
Investment, Identifier [Axis]: PPV Intermediate Holdings, LLC, One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (70) (70)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (70) [1],[5],[12]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     771 771    
Investments, at fair value, ending balance 606 [2],[10]     606 [2],[10]   771 [1],[5]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     34,892 34,892    
Investments, at fair value, ending balance 34,456 [2],[10],[11]     34,456 [2],[10],[11]   34,892 [1],[5],[16]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,292 4,292    
Investments, at fair value, ending balance 7,873 [2],[11]     7,873 [2],[11]   4,292 [1],[5]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     52 52    
Investments, at fair value, ending balance 18 [2],[10]     18 [2],[10]   52 [1],[5]
Investment, Identifier [Axis]: PPW Aero Buyer, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 6,448     6,448    
Investment, Identifier [Axis]: PSC Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     5,505 5,505    
Investments, at fair value, ending balance [1],[5],[16]           5,505
Investment, Identifier [Axis]: PSC Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     377 377    
Investments, at fair value, ending balance [1],[5]           377
Investment, Identifier [Axis]: PSC Parent, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: PSC Parent, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     917 917    
Investments, at fair value, ending balance [1],[5]           917
Investment, Identifier [Axis]: PSC Parent, Inc.., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 5,464     5,464    
Investment, Identifier [Axis]: PSC Parent, Inc.., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 276     276    
Investment, Identifier [Axis]: PSC Parent, Inc.., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 573     573    
Investment, Identifier [Axis]: PSC Parent, Inc.., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 911     911    
Investment, Identifier [Axis]: PT Intermediate Holdings III, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,879 1,879    
Investments, at fair value, ending balance 1,841 [2],[10]     1,841 [2],[10]   1,879 [1],[5]
Investment, Identifier [Axis]: PT Intermediate Holdings III, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     12,234 12,234    
Investments, at fair value, ending balance [1],[5],[9],[14]           12,234
Investment, Identifier [Axis]: PT Intermediate Holdings III, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: PT Intermediate Holdings III, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 18,796     18,796    
Investment, Identifier [Axis]: PT Intermediate Holdings III, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (17)     (17)    
Investment, Identifier [Axis]: Packaging Coordinators Midco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 5,272     5,272    
Investment, Identifier [Axis]: Packaging Coordinators Midco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Packaging Coordinators Midco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Packaging Coordinators Midco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Packaging Coordinators Midco, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Panzura, LLC, LLC Units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Panzura, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Panzura, LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     98 98    
Investments, at fair value, ending balance 116 [2],[10],[15]     116 [2],[10],[15]   98 [1],[5],[14]
Investment, Identifier [Axis]: Pareto Health Intermediate Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     22,115 22,115    
Investments, at fair value, ending balance 74,275 [2],[10],[11]     74,275 [2],[10],[11]   22,115 [1],[5],[17]
Investment, Identifier [Axis]: Pareto Health Intermediate Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     7,372 7,372    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   7,372 [1],[5]
Investment, Identifier [Axis]: Pareto Health Intermediate Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Patriot Growth Insurance Services, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     15,368 15,368    
Investments, at fair value, ending balance 72,212 [2],[10]     72,212 [2],[10]   15,368 [1],[5],[9],[17]
Investment, Identifier [Axis]: Patriot Growth Insurance Services, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,141 3,141    
Investments, at fair value, ending balance 9,847 [2],[10]     9,847 [2],[10]   3,141 [1],[5]
Investment, Identifier [Axis]: Patriot Growth Insurance Services, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     35 35    
Investments, at fair value, ending balance 2,849 [2],[10]     2,849 [2],[10]   35 [1],[5]
Investment, Identifier [Axis]: Patriot Growth Insurance Services, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,447 1,447    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   1,447 [1],[5]
Investment, Identifier [Axis]: People Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[9],[30]     24,688 24,688    
Investments, at fair value, ending balance 24,407 [2],[10],[25],[28],[32]     24,407 [2],[10],[25],[28],[32]   24,688 [1],[5],[7],[8],[9],[30]
Investment, Identifier [Axis]: People Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     20,716 20,716    
Investments, at fair value, ending balance 20,486 [2],[10],[25],[28],[32]     20,486 [2],[10],[25],[28],[32]   20,716 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: People Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     8,101 8,101    
Investments, at fair value, ending balance 10,020 [2],[10],[25],[28],[32]     10,020 [2],[10],[25],[28],[32]   8,101 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: People Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     6,802 6,802    
Investments, at fair value, ending balance 8,011 [2],[10],[25],[28],[32]     8,011 [2],[10],[25],[28],[32]   6,802 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: People Corporation, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[30]     71 71    
Investments, at fair value, ending balance 220 [2],[10],[25],[28],[32]     220 [2],[10],[25],[28],[32]   71 [1],[5],[7],[8],[30]
Investment, Identifier [Axis]: People Corporation, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 4,319     4,319    
Investment, Identifier [Axis]: Personify, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,303 2,303    
Investments, at fair value, ending balance 2,132 [2],[10]     2,132 [2],[10]   2,303 [1],[5]
Investment, Identifier [Axis]: Personify, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[18]     13,866 13,866    
Investments, at fair value, ending balance 18,530 [2],[10]     18,530 [2],[10]   13,866 [1],[5],[6],[16],[18]
Investment, Identifier [Axis]: Personify, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[17],[18]     9,810 9,810    
Investments, at fair value, ending balance 13,722 [2],[11]     13,722 [2],[11]   9,810 [1],[17],[18]
Investment, Identifier [Axis]: Personify, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 9,727 [2],[10],[11]     9,727 [2],[10],[11]   0 [1],[5]
Investment, Identifier [Axis]: Personify, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Pet Holdings ULC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[7],[8],[26]     657 657    
Investments, at fair value, ending balance [1],[5],[7],[8],[26]           657
Investment, Identifier [Axis]: PetVet Care Centers LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     4,503 4,503    
Investments, at fair value, ending balance 4,421 [2],[10],[11]     4,421 [2],[10],[11]   4,503 [1],[5],[16]
Investment, Identifier [Axis]: PetVet Care Centers LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance (6) [2],[10],[13]     (6) [2],[10],[13]   (4) [1],[5],[12]
Investment, Identifier [Axis]: PetVet Care Centers LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[44]     1,042 1,042    
Investments, at fair value, ending balance 14,858 [2],[10],[15],[25],[45]     14,858 [2],[10],[15],[25],[45]   1,042 [1],[5],[8],[14],[30],[44]
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[44]     247 247    
Investments, at fair value, ending balance 5,088 [2],[10],[15],[25],[32],[45]     5,088 [2],[10],[15],[25],[32],[45]   247 [1],[5],[8],[14],[30],[44]
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[30],[44]     72 72    
Investments, at fair value, ending balance 1,129 [2],[10],[15],[25],[32],[45]     1,129 [2],[10],[15],[25],[32],[45]   72 [1],[5],[8],[14],[30],[44]
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[32],[45] 350     350    
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[45] 76     76    
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15],[25],[32],[45] 78     78    
Investment, Identifier [Axis]: Pineapple German Bidco GMBH, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[32],[45] (125)     (125)    
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., LLC interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     866 866    
Investments, at fair value, ending balance 859 [2],[10]     859 [2],[10]   866 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., LLC interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,036 1,036    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   1,036 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     18,333 18,333    
Investments, at fair value, ending balance 18,183 [2],[11]     18,183 [2],[11]   18,333 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     103 103    
Investments, at fair value, ending balance 178 [2],[10]     178 [2],[10]   103 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     290 290    
Investments, at fair value, ending balance 102 [2],[10]     102 [2],[10]   290 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     12,277 12,277    
Investments, at fair value, ending balance 12,180 [2],[11]     12,180 [2],[11]   12,277 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,467 2,467    
Investments, at fair value, ending balance 2,449 [2],[10],[11]     2,449 [2],[10],[11]   2,467 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,383 2,383    
Investments, at fair value, ending balance 2,366 [2],[10]     2,366 [2],[10]   2,383 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,508 1,508    
Investments, at fair value, ending balance 1,496 [2],[10],[11]     1,496 [2],[10],[11]   1,508 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,368 1,368    
Investments, at fair value, ending balance 1,357 [2],[10],[11]     1,357 [2],[10],[11]   1,368 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     680 680    
Investments, at fair value, ending balance 675 [2],[10]     675 [2],[10]   680 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     533 533    
Investments, at fair value, ending balance 529 [2],[10]     529 [2],[10]   533 [1],[5]
Investment, Identifier [Axis]: Pinnacle Treatment Centers, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     180 180    
Investments, at fair value, ending balance 522 [2],[10]     522 [2],[10]   180 [1],[5]
Investment, Identifier [Axis]: PlanSource Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     14,091 14,091    
Investments, at fair value, ending balance 14,234 [2],[10],[11]     14,234 [2],[10],[11]   14,091 [1],[5],[9]
Investment, Identifier [Axis]: PlanSource Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,391 2,391    
Investments, at fair value, ending balance 2,416 [2],[10]     2,416 [2],[10]   2,391 [1],[5],[9]
Investment, Identifier [Axis]: PlanSource Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     689 689    
Investments, at fair value, ending balance 695 [2],[10]     695 [2],[10]   689 [1],[5]
Investment, Identifier [Axis]: PlanSource Holdings, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (3) (3)    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   (3) [1],[5],[12]
Investment, Identifier [Axis]: Plasma Buyer LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     7,795 7,795    
Investments, at fair value, ending balance 7,655 [2],[10]     7,655 [2],[10]   7,795 [1],[5],[9]
Investment, Identifier [Axis]: Plasma Buyer LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     173 173    
Investments, at fair value, ending balance 289 [2],[10]     289 [2],[10]   173 [1],[5]
Investment, Identifier [Axis]: Plasma Buyer LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     60 60    
Investments, at fair value, ending balance 108 [2],[10]     108 [2],[10]   60 [1],[5]
Investment, Identifier [Axis]: Pluralsight, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,663 3,663    
Investments, at fair value, ending balance 4,648 [2],[10]     4,648 [2],[10]   3,663 [1],[5]
Investment, Identifier [Axis]: Pluralsight, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     5,725 5,725    
Investments, at fair value, ending balance 6,475 [2],[10],[15]     6,475 [2],[10],[15]   5,725 [1],[5],[14]
Investment, Identifier [Axis]: Pluralsight, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,856 3,856    
Investments, at fair value, ending balance 3,979 [2],[10],[15]     3,979 [2],[10],[15]   3,856 [1],[5],[14]
Investment, Identifier [Axis]: Pluralsight, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,928 1,928    
Investments, at fair value, ending balance 1,990 [2],[10],[15]     1,990 [2],[10],[15]   1,928 [1],[5],[14]
Investment, Identifier [Axis]: Pluralsight, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (30) (30)    
Investments, at fair value, ending balance (10) [2],[10],[13]     (10) [2],[10],[13]   (30) [1],[5],[12]
Investment, Identifier [Axis]: Pluralsight, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (75) (75)    
Investments, at fair value, ending balance (25) [2],[10],[13]     (25) [2],[10],[13]   (75) [1],[5],[12]
Investment, Identifier [Axis]: Polk Acquisition Corp., LP Interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Polk Acquisition Corp., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 25     25    
Investment, Identifier [Axis]: Polk Acquisition Corp., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[14],[18]     17,297 17,297    
Investments, at fair value, ending balance [1],[5],[6],[14],[18]           17,297
Investment, Identifier [Axis]: Polk Acquisition Corp., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     102 102    
Investments, at fair value, ending balance [1],[5],[14]           102
Investment, Identifier [Axis]: Polk Acquisition Corp., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     108 108    
Investments, at fair value, ending balance [1],[5],[14]           108
Investment, Identifier [Axis]: Power Grid Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,425 1,425    
Investments, at fair value, ending balance 1,418 [2],[10]     1,418 [2],[10]   1,425 [1],[5],[9]
Investment, Identifier [Axis]: Power Grid Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 9 [2],[10]     9 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Premise Health Holding Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,391 1,391    
Investments, at fair value, ending balance 1,381 [2],[10]     1,381 [2],[10]   1,391 [1],[5],[9]
Investment, Identifier [Axis]: Premise Health Holding Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 6 [2],[10]     6 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: ProcessUnity Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     6,014 6,014    
Investments, at fair value, ending balance 6,014 [2],[10],[20]     6,014 [2],[10],[20]   6,014 [1],[5],[19]
Investment, Identifier [Axis]: ProcessUnity Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,864 2,864    
Investments, at fair value, ending balance 4,240 [2],[10]     4,240 [2],[10]   2,864 [1],[5],[9]
Investment, Identifier [Axis]: ProcessUnity Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,203 1,203    
Investments, at fair value, ending balance 2,864 [2],[10]     2,864 [2],[10]   1,203 [1],[5]
Investment, Identifier [Axis]: ProcessUnity Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     90 90    
Investments, at fair value, ending balance 1,203 [2],[10]     1,203 [2],[10]   90 [1],[5]
Investment, Identifier [Axis]: ProcessUnity Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 64     64    
Investment, Identifier [Axis]: Procure Acquireco, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,150 1,150    
Investments, at fair value, ending balance 1,216 [2],[10]     1,216 [2],[10]   1,150 [1],[5]
Investment, Identifier [Axis]: Procure Acquireco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17],[18]     24,925 24,925    
Investments, at fair value, ending balance 24,732 [2],[10],[11]     24,732 [2],[10],[11]   24,925 [1],[5],[16],[17],[18]
Investment, Identifier [Axis]: Procure Acquireco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,145 1,145    
Investments, at fair value, ending balance 1,137 [2],[10]     1,137 [2],[10]   1,145 [1],[5]
Investment, Identifier [Axis]: Procure Acquireco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Procure Acquireco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Procure Acquireco, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,470     3,470    
Investment, Identifier [Axis]: Profile Products LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,600 8,600    
Investments, at fair value, ending balance [1],[5],[9]           8,600
Investment, Identifier [Axis]: Profile Products LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9]     1,743 1,743    
Investments, at fair value, ending balance [1],[5],[8],[9]           1,743
Investment, Identifier [Axis]: Profile Products LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     68 68    
Investments, at fair value, ending balance [1],[5]           68
Investment, Identifier [Axis]: Profile Products LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance [1],[5],[12]           (4)
Investment, Identifier [Axis]: Profile Products LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 8,892     8,892    
Investment, Identifier [Axis]: Profile Products LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25] 1,802     1,802    
Investment, Identifier [Axis]: Profile Products LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 66     66    
Investment, Identifier [Axis]: Profile Products LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Project Alpha Intermediate Holdings, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     755 755    
Investments, at fair value, ending balance [1],[5]           755
Investment, Identifier [Axis]: Project Alpha Intermediate Holdings, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,359     1,359    
Investment, Identifier [Axis]: Project Alpha Intermediate Holdings, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,646 1,646    
Investments, at fair value, ending balance [1],[5],[26]           1,646
Investment, Identifier [Axis]: Project Nike Purchaser, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     33,529 33,529    
Investments, at fair value, ending balance 33,608 [2],[10],[11]     33,608 [2],[10],[11]   33,529 [1],[5],[17]
Investment, Identifier [Axis]: Project Nike Purchaser, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     742 742    
Investments, at fair value, ending balance 744 [2],[10]     744 [2],[10]   742 [1],[5],[9]
Investment, Identifier [Axis]: Project Nike Purchaser, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     246 246    
Investments, at fair value, ending balance 236 [2],[10]     236 [2],[10]   246 [1],[5]
Investment, Identifier [Axis]: Project Power Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[16],[18]     53,171 53,171    
Investments, at fair value, ending balance [1],[5],[6],[9],[16],[18]           53,171
Investment, Identifier [Axis]: Project Power Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: Provenance Buyer LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[16],[18]     19,756 19,756    
Investments, at fair value, ending balance 19,810 [2],[10],[11]     19,810 [2],[10],[11]   19,756 [1],[5],[6],[9],[16],[18]
Investment, Identifier [Axis]: Provenance Buyer LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[17],[18]     13,309 13,309    
Investments, at fair value, ending balance 13,346 [2],[10],[11]     13,346 [2],[10],[11]   13,309 [1],[17],[18]
Investment, Identifier [Axis]: Provenance Buyer LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     112 112    
Investments, at fair value, ending balance 178 [2],[10]     178 [2],[10]   112 [1],[5]
Investment, Identifier [Axis]: Purfoods, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,991 4,991    
Investments, at fair value, ending balance 5,513 [2],[10]     5,513 [2],[10]   4,991 [1],[5]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp, Common Stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     385 385    
Investments, at fair value, ending balance [1],[5]           385
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 392     392    
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17],[18]     25,098 25,098    
Investments, at fair value, ending balance 24,904 [2],[10],[11]     24,904 [2],[10],[11]   25,098 [1],[5],[17],[18]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     202 202    
Investments, at fair value, ending balance 201 [2],[10]     201 [2],[10]   202 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     79 79    
Investments, at fair value, ending balance 79 [2],[10]     79 [2],[10]   79 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,595 2,595    
Investments, at fair value, ending balance 2,575 [2],[10],[11]     2,575 [2],[10],[11]   2,595 [1],[5]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,170 2,170    
Investments, at fair value, ending balance 2,153 [2],[10],[11]     2,153 [2],[10],[11]   2,170 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,192 1,192    
Investments, at fair value, ending balance 1,184 [2],[10]     1,184 [2],[10]   1,192 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,092 1,092    
Investments, at fair value, ending balance 1,083 [2],[10]     1,083 [2],[10]   1,092 [1],[5]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     738 738    
Investments, at fair value, ending balance 732 [2],[10]     732 [2],[10]   738 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     245 245    
Investments, at fair value, ending balance 243 [2],[10]     243 [2],[10]   245 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     216 216    
Investments, at fair value, ending balance 214 [2],[10]     214 [2],[10]   216 [1],[5],[9]
Investment, Identifier [Axis]: Pyramid Healthcare Acquisition Corp., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     202 202    
Investments, at fair value, ending balance 201 [2],[10]     201 [2],[10]   202 [1],[5],[9]
Investment, Identifier [Axis]: QAD, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 40 [2],[10]     40 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: QAD, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     43,261 43,261    
Investments, at fair value, ending balance 42,929 [2],[10],[11]     42,929 [2],[10],[11]   43,261 [1],[5],[9],[17]
Investment, Identifier [Axis]: QAD, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: QAD, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,147 1,147    
Investments, at fair value, ending balance 1,326 [2],[10],[27]     1,326 [2],[10],[27]   1,147 [1],[5],[26]
Investment, Identifier [Axis]: QF Holdings, Inc., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     931 931    
Investments, at fair value, ending balance 927 [2],[10]     927 [2],[10]   931 [1],[5]
Investment, Identifier [Axis]: QSR Acquisition Co., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,520     1,520    
Investment, Identifier [Axis]: QSR Acquisition Co., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: QSR Acquisition Co., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: Quant Buyer, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     7,406 7,406    
Investments, at fair value, ending balance 7,350 [2],[10],[11]     7,350 [2],[10],[11]   7,406 [1],[5],[9]
Investment, Identifier [Axis]: Quant Buyer, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,360 4,360    
Investments, at fair value, ending balance 4,439 [2],[10],[11]     4,439 [2],[10],[11]   4,360 [1],[5],[9]
Investment, Identifier [Axis]: Quant Buyer, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     3,015 3,015    
Investments, at fair value, ending balance 4,327 [2],[10],[11]     4,327 [2],[10],[11]   3,015 [1],[5],[16]
Investment, Identifier [Axis]: Quant Buyer, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 170 [2],[10]     170 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Quant Buyer, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     226 226    
Investments, at fair value, ending balance 259 [2],[10]     259 [2],[10]   226 [1],[5]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,143 1,143    
Investments, at fair value, ending balance 1,363 [2],[10]     1,363 [2],[10]   1,143 [1],[5]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     3,608 3,608    
Investments, at fair value, ending balance 4,593 [2],[10]     4,593 [2],[10]   3,608 [1],[5]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     140 140    
Investments, at fair value, ending balance 358 [2],[10]     358 [2],[10]   140 [1],[5]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Quick Quack Car Wash Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (4)     (4)    
Investment, Identifier [Axis]: RJW Group Holdings, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 4,716     4,716    
Investment, Identifier [Axis]: RJW Group Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 46,415     46,415    
Investment, Identifier [Axis]: RJW Group Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: RPL Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     6,052 6,052    
Investments, at fair value, ending balance 6,213 [2],[10],[25],[31],[32]     6,213 [2],[10],[25],[31],[32]   6,052 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: RPL Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     27,932 27,932    
Investments, at fair value, ending balance 28,676 [2],[10],[25],[31],[32]     28,676 [2],[10],[25],[31],[32]   27,932 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: RPL Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     12,173 12,173    
Investments, at fair value, ending balance 11,586 [2],[10],[25],[31],[32]     11,586 [2],[10],[25],[31],[32]   12,173 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: RPL Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     2,955 2,955    
Investments, at fair value, ending balance 2,812 [2],[10],[25],[31],[32]     2,812 [2],[10],[25],[31],[32]   2,955 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: RPL Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[31],[32]     0 [2],[10],[25],[31],[32]   0 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: RW AM Holdco LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17],[18]     24,523 24,523    
Investments, at fair value, ending balance 19,835 [2],[10]     19,835 [2],[10]   24,523 [1],[5],[17],[18]
Investment, Identifier [Axis]: RW AM Holdco LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (22) (22)    
Investments, at fair value, ending balance (32) [2],[10],[13]     (32) [2],[10],[13]   (22) [1],[5],[12]
Investment, Identifier [Axis]: Radiance Borrower, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     21,558 21,558    
Investments, at fair value, ending balance 21,850 [2],[10],[15]     21,850 [2],[10],[15]   21,558 [1],[5],[14]
Investment, Identifier [Axis]: Radiance Borrower, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     410 410    
Investments, at fair value, ending balance 205 [2],[10]     205 [2],[10]   410 [1],[5]
Investment, Identifier [Axis]: Radiology Partners, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     340 340    
Investments, at fair value, ending balance 360 [2],[10]     360 [2],[10]   340 [1],[5]
Investment, Identifier [Axis]: Radiology Partners, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     86 86    
Investments, at fair value, ending balance 91 [2],[10]     91 [2],[10]   86 [1],[5]
Investment, Identifier [Axis]: Radwell Parent, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     465 465    
Investments, at fair value, ending balance 415 [2],[10]     415 [2],[10]   465 [1],[5]
Investment, Identifier [Axis]: Radwell Parent, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[18],[19]     33,947 33,947    
Investments, at fair value, ending balance [1],[5],[18],[19]           33,947
Investment, Identifier [Axis]: Radwell Parent, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[17]     32,083 32,083    
Investments, at fair value, ending balance [1],[5],[9],[17]           32,083
Investment, Identifier [Axis]: Radwell Parent, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     235 235    
Investments, at fair value, ending balance [1],[5]           235
Investment, Identifier [Axis]: Radwell Parent, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     540 540    
Investments, at fair value, ending balance [1],[5]           540
Investment, Identifier [Axis]: Radwell Parent, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11],[20] 34,027     34,027    
Investment, Identifier [Axis]: Radwell Parent, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[11] 32,707     32,707    
Investment, Identifier [Axis]: Radwell Parent, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 371     371    
Investment, Identifier [Axis]: Rainforest Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29],[30]     19,962 19,962    
Investments, at fair value, ending balance 21,610 [2],[10],[15],[25],[31],[32]     21,610 [2],[10],[15],[25],[31],[32]   19,962 [1],[5],[8],[14],[29],[30]
Investment, Identifier [Axis]: Rainforest Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29]     3,526 3,526    
Investments, at fair value, ending balance 3,720 [2],[10],[15],[25],[31]     3,720 [2],[10],[15],[25],[31]   3,526 [1],[5],[8],[14],[29]
Investment, Identifier [Axis]: Rainforest Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29],[30]     2,159 2,159    
Investments, at fair value, ending balance 2,269 [2],[10],[15],[25],[31],[32]     2,269 [2],[10],[15],[25],[31],[32]   2,159 [1],[5],[8],[14],[29],[30]
Investment, Identifier [Axis]: Rainforest Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29],[30]     1,467 1,467    
Investments, at fair value, ending balance 1,588 [2],[10],[15],[25],[31],[32]     1,588 [2],[10],[15],[25],[31],[32]   1,467 [1],[5],[8],[14],[29],[30]
Investment, Identifier [Axis]: Rainforest Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 999     999    
Investment, Identifier [Axis]: Reaction Biology Corporation            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     0 0    
Gross additions       10,227    
Gross reductions       (1,707)    
Net change in unrealized appreciation (depreciation)       (957)    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 7,563     7,563   0
Interest, dividend and fee income       94    
Investment, Identifier [Axis]: Reaction Biology Corporation, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4 4    
Investments, at fair value, ending balance 4,137 [2],[10]     4,137 [2],[10]   4 [1],[5]
Investment, Identifier [Axis]: Reaction Biology Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[18],[21]     6,622 6,622    
Investments, at fair value, ending balance 2,743 [2],[10],[15]     2,743 [2],[10],[15]   6,622 [1],[5],[14],[18],[21]
Investment, Identifier [Axis]: Reaction Biology Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     2,203 2,203    
Investments, at fair value, ending balance 683 [2],[10],[15]     683 [2],[10],[15]   2,203 [1],[5],[14],[21]
Investment, Identifier [Axis]: Reaction Biology Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     1,465 1,465    
Investments, at fair value, ending balance [1],[5],[14],[21]           1,465
Investment, Identifier [Axis]: Reaction Biology Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     236 236    
Investments, at fair value, ending balance [1],[5],[14],[21]           236
Investment, Identifier [Axis]: Recordxtechnologies, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16],[18]     18,874 18,874    
Investments, at fair value, ending balance 18,727 [2],[10],[11]     18,727 [2],[10],[11]   18,874 [1],[9],[16],[18]
Investment, Identifier [Axis]: Recordxtechnologies, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,769 1,769    
Investments, at fair value, ending balance 12,458 [2],[11]     12,458 [2],[11]   1,769 [1],[5]
Investment, Identifier [Axis]: Recordxtechnologies, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2 2    
Investments, at fair value, ending balance 1,755 [2],[10]     1,755 [2],[10]   2 [1],[5]
Investment, Identifier [Axis]: Recordxtechnologies, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     894 894    
Investments, at fair value, ending balance 887 [2],[10]     887 [2],[10]   894 [1],[5],[9]
Investment, Identifier [Axis]: Recordxtechnologies, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     12,553 12,553    
Investments, at fair value, ending balance 2 [2],[10]     2 [2],[10]   12,553 [1],[5]
Investment, Identifier [Axis]: RegEd Aquireco, LLC, LP interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     163 163    
Investments, at fair value, ending balance 168 [2],[10]     168 [2],[10]   163 [1],[5]
Investment, Identifier [Axis]: RegEd Aquireco, LLC, LP interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: RegEd Aquireco, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     32 32    
Investments, at fair value, ending balance 37 [2],[10]     37 [2],[10]   32 [1],[5]
Investment, Identifier [Axis]: ReliaQuest Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     11,710 11,710    
Investments, at fair value, ending balance 11,972 [2],[10],[15]     11,972 [2],[10],[15]   11,710 [1],[5],[9],[14]
Investment, Identifier [Axis]: ReliaQuest Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (5) [2],[10],[13]     (5) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: ReliaQuest Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (23) [2],[10],[13]     (23) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: ReliaQuest Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 28,514     28,514    
Investment, Identifier [Axis]: Revalize, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[19]     19,279 19,279    
Investments, at fair value, ending balance 17,705 [2],[10],[20]     17,705 [2],[10],[20]   19,279 [1],[5],[16],[19]
Investment, Identifier [Axis]: Revalize, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     11,284 11,284    
Investments, at fair value, ending balance 10,363 [2],[10],[20]     10,363 [2],[10],[20]   11,284 [1],[5],[19]
Investment, Identifier [Axis]: Revalize, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     5,595 5,595    
Investments, at fair value, ending balance 5,138 [2],[10],[20]     5,138 [2],[10],[20]   5,595 [1],[5],[19]
Investment, Identifier [Axis]: Revalize, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     3,370 3,370    
Investments, at fair value, ending balance 3,096 [2],[10],[20]     3,096 [2],[10],[20]   3,370 [1],[5],[19]
Investment, Identifier [Axis]: Revalize, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,294 2,294    
Investments, at fair value, ending balance 2,107 [2],[10]     2,107 [2],[10]   2,294 [1],[5],[9]
Investment, Identifier [Axis]: Revalize, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,253 2,253    
Investments, at fair value, ending balance 2,069 [2],[10]     2,069 [2],[10]   2,253 [1],[5],[9]
Investment, Identifier [Axis]: Revalize, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     219 219    
Investments, at fair value, ending balance 198 [2],[10]     198 [2],[10]   219 [1],[5]
Investment, Identifier [Axis]: Revalize, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     224 224    
Investments, at fair value, ending balance 306 [2],[10]     306 [2],[10]   224 [1],[5]
Investment, Identifier [Axis]: Revalize, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     30,067 30,067    
Investments, at fair value, ending balance 20,134 [2],[10]     20,134 [2],[10]   30,067 [1],[5]
Investment, Identifier [Axis]: Revalize, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     18,046 18,046    
Investments, at fair value, ending balance 12,085 [2],[10]     12,085 [2],[10]   18,046 [1],[5]
Investment, Identifier [Axis]: Revalize, Inc., Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     11,768 11,768    
Investments, at fair value, ending balance 7,885 [2],[10]     7,885 [2],[10]   11,768 [1],[5]
Investment, Identifier [Axis]: Revalize, Inc., Preferred stock 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     4,481 4,481    
Investments, at fair value, ending balance 3,001 [2],[10]     3,001 [2],[10]   4,481 [1],[5]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,513 1,513    
Investments, at fair value, ending balance 1,429 [2],[10]     1,429 [2],[10]   1,513 [1],[5]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9]     45,407 45,407    
Investments, at fair value, ending balance 44,832 [2],[10],[11]     44,832 [2],[10],[11]   45,407 [1],[5],[6],[9]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,131 2,131    
Investments, at fair value, ending balance 2,103 [2],[10]     2,103 [2],[10]   2,131 [1],[5]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     815 815    
Investments, at fair value, ending balance 809 [2],[10]     809 [2],[10]   815 [1],[5],[9]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     573 573    
Investments, at fair value, ending balance 569 [2],[10]     569 [2],[10]   573 [1],[5]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (4) (4)    
Investments, at fair value, ending balance 68 [2],[10]     68 [2],[10]   (4) [1],[5],[12]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (10) (10)    
Investments, at fair value, ending balance (10) [2],[10],[13]     (10) [2],[10],[13]   (10) [1],[5],[12]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     31,936 31,936    
Investments, at fair value, ending balance 35,515 [2],[10],[27]     35,515 [2],[10],[27]   31,936 [1],[5],[26]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     934 934    
Investments, at fair value, ending balance 1,034 [2],[10],[27]     1,034 [2],[10],[27]   934 [1],[5],[26]
Investment, Identifier [Axis]: Riskonnect Parent, LLC, Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     52 52    
Investments, at fair value, ending balance 58 [2],[10],[27]     58 [2],[10],[27]   52 [1],[5],[26]
Investment, Identifier [Axis]: Rodeo Buyer Company & Absorb Software Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[19]     7,616 7,616    
Investments, at fair value, ending balance 13,056 [2],[10],[25],[28]     13,056 [2],[10],[25],[28]   7,616 [1],[5],[9],[19]
Investment, Identifier [Axis]: Rodeo Buyer Company & Absorb Software Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 7,616 [2],[10],[20],[25],[28]     7,616 [2],[10],[20],[25],[28]   0 [1],[5]
Investment, Identifier [Axis]: Rodeo Buyer Company & Absorb Software Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 0     0    
Investment, Identifier [Axis]: Rodeo Buyer Company & Absorb Software Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 2,000     2,000    
Investment, Identifier [Axis]: Rokt Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 718     718    
Investment, Identifier [Axis]: Rooster BidCo Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 5,090     5,090    
Investment, Identifier [Axis]: Rooster BidCo Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 0     0    
Investment, Identifier [Axis]: Rooster BidCo Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31],[32] 0     0    
Investment, Identifier [Axis]: Rooster BidCo Limited, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 1,301     1,301    
Investment, Identifier [Axis]: Royal Holdco Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 5,996     5,996    
Investment, Identifier [Axis]: Royal Holdco Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Royal Holdco Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 241     241    
Investment, Identifier [Axis]: Rubio's Restaurants, Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     0 0 12,063 12,063
Gross additions           3,759
Gross reductions           (3,929)
Net change in unrealized appreciation (depreciation)           6,624
Net realized gain (loss)           (18,517)
Investments, at fair value, ending balance           0
Interest, dividend and fee income           1,187
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, LLC interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     174 174    
Investments, at fair value, ending balance 112 [2],[10]     112 [2],[10]   174 [1],[5]
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, LLC interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     46 46    
Investments, at fair value, ending balance 52 [2],[10]     52 [2],[10]   46 [1],[5]
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     49 49    
Investments, at fair value, ending balance 52 [2],[10]     52 [2],[10]   49 [1],[5]
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6]     2,304 2,304    
Investments, at fair value, ending balance [1],[5],[6]           2,304
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     515 515    
Investments, at fair value, ending balance [1],[5]           515
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     340 340    
Investments, at fair value, ending balance [1],[5]           340
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     190 190    
Investments, at fair value, ending balance [1],[5]           190
Investment, Identifier [Axis]: Ruby Slipper Cafe LLC, The, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance [1],[5]           0
Investment, Identifier [Axis]: S.J. Electro Systems, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     24,226 24,226    
Investments, at fair value, ending balance 24,165 [2],[11]     24,165 [2],[11]   24,226 [1],[5]
Investment, Identifier [Axis]: S.J. Electro Systems, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16],[17]     18,635 18,635    
Investments, at fair value, ending balance 18,538 [2],[10],[11]     18,538 [2],[10],[11]   18,635 [1],[9],[16],[17]
Investment, Identifier [Axis]: S.J. Electro Systems, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,176 1,176    
Investments, at fair value, ending balance 1,169 [2],[10]     1,169 [2],[10]   1,176 [1],[5],[9]
Investment, Identifier [Axis]: S.J. Electro Systems, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (63) (63)    
Investments, at fair value, ending balance (43) [2],[10],[13]     (43) [2],[10],[13]   (63) [1],[5],[12]
Investment, Identifier [Axis]: S.J. Electro Systems, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (5)     (5)    
Investment, Identifier [Axis]: SC Landco Parent, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     260 260    
Investments, at fair value, ending balance 259 [2],[10]     259 [2],[10]   260 [1],[5]
Investment, Identifier [Axis]: SDC Holdco, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     21,737 21,737    
Investments, at fair value, ending balance 21,737 [2],[11]     21,737 [2],[11]   21,737 [1],[5]
Investment, Identifier [Axis]: SDC Holdco, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     192 192    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   192 [1],[5]
Investment, Identifier [Axis]: SDC Holdco, LLC, Second lien            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,340 3,340    
Investments, at fair value, ending balance 3,678 [2],[10],[15]     3,678 [2],[10],[15]   3,340 [1],[5],[14]
Investment, Identifier [Axis]: SPF Borrower LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     36,653 36,653    
Gross additions       538    
Gross reductions       (246)    
Net change in unrealized appreciation (depreciation)       393    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 37,338     37,338   36,653
Interest, dividend and fee income       2,239    
Investment, Identifier [Axis]: SPF Borrower LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     12,129 12,129    
Investments, at fair value, ending balance 12,522 [2],[10]     12,522 [2],[10]   12,129 [1],[5]
Investment, Identifier [Axis]: SPF Borrower LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     16,191 16,191    
Investments, at fair value, ending balance 16,191 [2],[10],[15]     16,191 [2],[10],[15]   16,191 [1],[5],[14]
Investment, Identifier [Axis]: SPF Borrower LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     8,333 8,333    
Investments, at fair value, ending balance 8,625 [2],[10],[15]     8,625 [2],[10],[15]   8,333 [1],[5],[14]
Investment, Identifier [Axis]: SPF Borrower LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: SSRG Holdings, LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     566 566    
Investments, at fair value, ending balance 650 [2],[10]     650 [2],[10]   566 [1],[5],[26]
Investment, Identifier [Axis]: SSRG Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     12,470 12,470    
Investments, at fair value, ending balance 12,439 [2],[11]     12,439 [2],[11]   12,470 [1],[5]
Investment, Identifier [Axis]: SSRG Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17]     7,744 7,744    
Investments, at fair value, ending balance 7,722 [2],[10],[11]     7,722 [2],[10],[11]   7,744 [1],[5],[16],[17]
Investment, Identifier [Axis]: SSRG Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     804 804    
Investments, at fair value, ending balance 1,272 [2],[10]     1,272 [2],[10]   804 [1],[5]
Investment, Identifier [Axis]: SSRG Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     611 611    
Investments, at fair value, ending balance 610 [2],[10]     610 [2],[10]   611 [1],[5],[9]
Investment, Identifier [Axis]: Sage Dental Management, LLC, LLC units 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     617 617    
Investments, at fair value, ending balance 486 [2],[10]     486 [2],[10]   617 [1],[5]
Investment, Identifier [Axis]: Sage Dental Management, LLC, LLC units 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: SailPoint Technologies Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     14,654 14,654    
Investments, at fair value, ending balance [1],[5],[19]           14,654
Investment, Identifier [Axis]: SailPoint Technologies Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Salon Lofts Group, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     112 112    
Investments, at fair value, ending balance 106 [2],[10]     106 [2],[10]   112 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     3,045 3,045    
Investments, at fair value, ending balance 3,390 [2],[10],[15]     3,390 [2],[10],[15]   3,045 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,615 1,615    
Investments, at fair value, ending balance 1,799 [2],[10],[15]     1,799 [2],[10],[15]   1,615 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     578 578    
Investments, at fair value, ending balance 1,511 [2],[10],[15]     1,511 [2],[10],[15]   578 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     786 786    
Investments, at fair value, ending balance 879 [2],[10],[15]     879 [2],[10],[15]   786 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     150 150    
Investments, at fair value, ending balance 655 [2],[10],[15]     655 [2],[10],[15]   150 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     304 304    
Investments, at fair value, ending balance 167 [2],[10],[15]     167 [2],[10],[15]   304 [1],[5],[14]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[15] 26     26    
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Second lien 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 670     670    
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,256 5,256    
Investments, at fair value, ending balance 5,242 [2],[10]     5,242 [2],[10]   5,256 [1],[5],[9]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     80 80    
Investments, at fair value, ending balance 155 [2],[10]     155 [2],[10]   80 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 11            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 113 [2],[10]     113 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 12            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 105 [2],[10]     105 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 13            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 86 [2],[10]     86 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 14            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     170 170    
Investments, at fair value, ending balance 79 [2],[10]     79 [2],[10]   170 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 15            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 639     639    
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 16            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 17            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,233     2,233    
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     540 540    
Investments, at fair value, ending balance 539 [2],[10]     539 [2],[10]   540 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     349 349    
Investments, at fair value, ending balance 500 [2],[10]     500 [2],[10]   349 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     344 344    
Investments, at fair value, ending balance 351 [2],[10]     351 [2],[10]   344 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     272 272    
Investments, at fair value, ending balance 342 [2],[10]     342 [2],[10]   272 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     156 156    
Investments, at fair value, ending balance 383 [2],[10]     383 [2],[10]   156 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     114 114    
Investments, at fair value, ending balance 271 [2],[10]     271 [2],[10]   114 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     105 105    
Investments, at fair value, ending balance 249 [2],[10]     249 [2],[10]   105 [1],[5]
Investment, Identifier [Axis]: Salon Lofts Group, LLC, Senior secured 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     86 86    
Investments, at fair value, ending balance 169 [2],[10]     169 [2],[10]   86 [1],[5]
Investment, Identifier [Axis]: Sapphire Bidco Oy, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[51]     50,901 50,901    
Investments, at fair value, ending balance 53,853 [2],[10],[25],[32],[50]     53,853 [2],[10],[25],[32],[50]   50,901 [1],[5],[8],[30],[51]
Investment, Identifier [Axis]: Sapphire Bidco Oy, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[51]     4,170 4,170    
Investments, at fair value, ending balance 4,401 [2],[10],[25],[32],[50]     4,401 [2],[10],[25],[32],[50]   4,170 [1],[5],[8],[30],[51]
Investment, Identifier [Axis]: Sapphire Bidco Oy, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[30],[51]     1,537 1,537    
Investments, at fair value, ending balance 1,626 [2],[10],[25],[32],[50]     1,626 [2],[10],[25],[32],[50]   1,537 [1],[5],[8],[9],[30],[51]
Investment, Identifier [Axis]: Saturn Borrower Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     267 267    
Investments, at fair value, ending balance 698 [2],[10]     698 [2],[10]   267 [1],[5]
Investment, Identifier [Axis]: Saturn Borrower Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16]     26,983 26,983    
Investments, at fair value, ending balance 27,395 [2],[10],[11]     27,395 [2],[10],[11]   26,983 [1],[5],[9],[16]
Investment, Identifier [Axis]: Saturn Borrower Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     434 434    
Investments, at fair value, ending balance 49 [2],[10]     49 [2],[10]   434 [1],[5]
Investment, Identifier [Axis]: Severin Acquisition, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 35,261     35,261    
Investment, Identifier [Axis]: Severin Acquisition, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,882     1,882    
Investment, Identifier [Axis]: Severin Acquisition, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 903     903    
Investment, Identifier [Axis]: Shoes For Crews Global, LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,109 1,109    
Investments, at fair value, ending balance 1,233 [2],[10]     1,233 [2],[10]   1,109 [1],[5]
Investment, Identifier [Axis]: Shoes For Crews Global, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,302 1,302    
Investments, at fair value, ending balance 1,292 [2],[10]     1,292 [2],[10]   1,302 [1],[5]
Investment, Identifier [Axis]: Shoes For Crews Global, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     688 688    
Investments, at fair value, ending balance 747 [2],[10],[15]     747 [2],[10],[15]   688 [1],[5],[14]
Investment, Identifier [Axis]: Shoes For Crews Global, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     421 421    
Investments, at fair value, ending balance 418 [2],[10]     418 [2],[10]   421 [1],[5]
Investment, Identifier [Axis]: Shoes For Crews Global, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Shout! Factory, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,763     1,763    
Investment, Identifier [Axis]: Shout! Factory, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (3)     (3)    
Investment, Identifier [Axis]: Sloan Company, Inc.            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     36,653 36,653 0 0
Gross additions           34,008
Gross reductions           (136)
Net change in unrealized appreciation (depreciation)           2,781
Net realized gain (loss)           0
Investments, at fair value, ending balance           36,653
Interest, dividend and fee income           2,112
Investment, Identifier [Axis]: Smart Energy Systems, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 6,235     6,235    
Investment, Identifier [Axis]: Smart Energy Systems, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 674     674    
Investment, Identifier [Axis]: Smart Energy Systems, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 375     375    
Investment, Identifier [Axis]: SnapLogic, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,707 1,707    
Investments, at fair value, ending balance 2,007 [2],[10]     2,007 [2],[10]   1,707 [1],[5]
Investment, Identifier [Axis]: SnapLogic, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     439 439    
Investments, at fair value, ending balance 517 [2],[10]     517 [2],[10]   439 [1],[5]
Investment, Identifier [Axis]: Sonatype, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     55,697 55,697    
Investments, at fair value, ending balance 69,460 [2],[10],[20]     69,460 [2],[10],[20]   55,697 [1],[5],[9]
Investment, Identifier [Axis]: Sonatype, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     13,763 13,763    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   13,763 [1],[5],[19]
Investment, Identifier [Axis]: Sonatype, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 268     268    
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 22     22    
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3     3    
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 0     0    
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5,022 5,022    
Investments, at fair value, ending balance [1],[5]           5,022
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC, Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     7,200 7,200    
Investments, at fair value, ending balance 5,194 [2],[10],[27]     5,194 [2],[10],[27]   7,200 [1],[5],[26]
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC, Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,360 1,360    
Investments, at fair value, ending balance 432 [2],[10],[27]     432 [2],[10],[27]   1,360 [1],[5],[26]
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC, Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 51     51    
Investment, Identifier [Axis]: Southern Veterinary Partners, LLC, Preferred stock 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[27] 4     4    
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[29],[30]     36,204 36,204    
Investments, at fair value, ending balance 37,778 [2],[10],[15],[25],[31],[32]     37,778 [2],[10],[15],[25],[31],[32]   36,204 [1],[5],[8],[9],[14],[29],[30]
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     5,558 5,558    
Investments, at fair value, ending balance 5,706 [2],[10],[25],[31],[32]     5,706 [2],[10],[25],[31],[32]   5,558 [1],[5],[8],[9],[29],[30]
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29],[30]     4,388 4,388    
Investments, at fair value, ending balance 4,579 [2],[10],[15],[25],[31],[32]     4,579 [2],[10],[15],[25],[31],[32]   4,388 [1],[5],[8],[14],[29],[30]
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29]     3,991 3,991    
Investments, at fair value, ending balance 3,991 [2],[10],[25],[31]     3,991 [2],[10],[25],[31]   3,991 [1],[5],[8],[29]
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[29],[30]     3,840 3,840    
Investments, at fair value, ending balance 4,007 [2],[10],[15],[25],[31],[32]     4,007 [2],[10],[15],[25],[31],[32]   3,840 [1],[5],[8],[14],[29],[30]
Investment, Identifier [Axis]: Spark Bidco Limited, Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     (8) (8)    
Investments, at fair value, ending balance 118 [2],[10],[25],[31],[32]     118 [2],[10],[25],[31],[32]   (8) [1],[5],[8],[12],[29],[30]
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     132 132    
Investments, at fair value, ending balance [1],[5]           132
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     584 584    
Investments, at fair value, ending balance 414 [2],[10]     414 [2],[10]   584 [1],[5]
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[14],[18],[19]     44,251 44,251    
Investments, at fair value, ending balance 44,370 [2],[10],[11],[15],[20]     44,370 [2],[10],[11],[15],[20]   44,251 [1],[5],[6],[9],[14],[18],[19]
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     2,820 2,820    
Investments, at fair value, ending balance 2,822 [2],[10],[15]     2,822 [2],[10],[15]   2,820 [1],[5],[9],[14]
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12],[14]     (2) (2)    
Investments, at fair value, ending balance (2) [2],[10],[13],[15]     (2) [2],[10],[13],[15]   (2) [1],[5],[12],[14]
Investment, Identifier [Axis]: Spartan Buyer Acquisition Co., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 131     131    
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     11,146 11,146    
Investments, at fair value, ending balance [1],[5],[8],[9],[29]           11,146
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29],[30]     10,428 10,428    
Investments, at fair value, ending balance [1],[5],[8],[9],[29],[30]           10,428
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     5,129 5,129    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           5,129
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     2,040 2,040    
Investments, at fair value, ending balance [1],[5],[8],[9],[29]           2,040
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     3,805 3,805    
Investments, at fair value, ending balance [1],[5],[8],[9],[29]           3,805
Investment, Identifier [Axis]: Specialty Measurement Bidco Limited, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     4,588 4,588    
Investments, at fair value, ending balance [1],[5],[8],[29],[30]           4,588
Investment, Identifier [Axis]: Spindrift Beverage Co. Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,231     2,231    
Investment, Identifier [Axis]: Spindrift Beverage Co. Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 7,653     7,653    
Investment, Identifier [Axis]: Spindrift Beverage Co. Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 105     105    
Investment, Identifier [Axis]: Spindrift Beverage Co. Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Stellar Brands, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 7,169     7,169    
Investment, Identifier [Axis]: Stellar Brands, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: StrongDM, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,257     2,257    
Investment, Identifier [Axis]: Super REGO, LLC, Subordinated debt            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     108 108    
Investments, at fair value, ending balance 72 [2],[10],[15]     72 [2],[10],[15]   108 [1],[5],[14]
Investment, Identifier [Axis]: Surewerx Purchaser III, Inc. & Jet Equipment & Tools Ltd., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[16],[17],[19]     29,510 29,510    
Investments, at fair value, ending balance 30,610 [2],[10],[11],[20],[25],[28]     30,610 [2],[10],[11],[20],[25],[28]   29,510 [1],[5],[8],[9],[16],[17],[19]
Investment, Identifier [Axis]: Surewerx Purchaser III, Inc. & Jet Equipment & Tools Ltd., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[30]     8,039 8,039    
Investments, at fair value, ending balance 7,851 [2],[10],[25],[28],[32]     7,851 [2],[10],[25],[28],[32]   8,039 [1],[5],[8],[9],[30]
Investment, Identifier [Axis]: Surewerx Purchaser III, Inc. & Jet Equipment & Tools Ltd., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8]     501 501    
Investments, at fair value, ending balance 1,186 [2],[10],[25],[28]     1,186 [2],[10],[25],[28]   501 [1],[5],[8]
Investment, Identifier [Axis]: Surewerx Purchaser III, Inc. & Jet Equipment & Tools Ltd., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12]     0 0    
Investments, at fair value, ending balance 325 [2],[10],[25],[28]     325 [2],[10],[25],[28]   0 [1],[5],[8],[12]
Investment, Identifier [Axis]: Suveto Buyer, LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 523     523    
Investment, Identifier [Axis]: Suveto Buyer, LLC, Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     534 534    
Investments, at fair value, ending balance [1],[5]           534
Investment, Identifier [Axis]: Suveto Buyer, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     27,639 27,639    
Investments, at fair value, ending balance 27,530 [2],[10],[11]     27,530 [2],[10],[11]   27,639 [1],[5]
Investment, Identifier [Axis]: Suveto Buyer, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     194 194    
Investments, at fair value, ending balance 8,077 [2],[10]     8,077 [2],[10]   194 [1],[5]
Investment, Identifier [Axis]: Suveto Buyer, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Switchfly LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     7,313 7,313    
Gross additions       713    
Gross reductions       0    
Net change in unrealized appreciation (depreciation)       376    
Net realized gain (loss)       0    
Investments, at fair value, ending balance 8,402     8,402   7,313
Interest, dividend and fee income       22    
Investment, Identifier [Axis]: Switchfly LLC            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance     7,313 7,313 $ 7,254 7,254
Gross additions           6,180
Gross reductions           (5,378)
Net change in unrealized appreciation (depreciation)           1,157
Net realized gain (loss)           (1,900)
Investments, at fair value, ending balance           7,313
Interest, dividend and fee income           88
Investment, Identifier [Axis]: Switchfly LLC, LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     860 860    
Investments, at fair value, ending balance 811 [2],[10]     811 [2],[10]   860 [1],[5]
Investment, Identifier [Axis]: Switchfly LLC, LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     552 552    
Investments, at fair value, ending balance 587 [2],[10]     587 [2],[10]   552 [1],[5]
Investment, Identifier [Axis]: Switchfly LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 1,281     1,281    
Investment, Identifier [Axis]: Switchfly LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     526 526    
Investments, at fair value, ending balance [1],[5],[14]           526
Investment, Identifier [Axis]: Switchfly LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     5,375 5,375    
Investments, at fair value, ending balance 5,723 [2],[10]     5,723 [2],[10]   5,375 [1],[5]
Investment, Identifier [Axis]: Symplr Software, Inc., Common stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,064 1,064    
Investments, at fair value, ending balance 789 [2],[10]     789 [2],[10]   1,064 [1],[5]
Investment, Identifier [Axis]: Symplr Software, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     185 185    
Investments, at fair value, ending balance 138 [2],[10]     138 [2],[10]   185 [1],[5]
Investment, Identifier [Axis]: Symplr Software, Inc., Preferred stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     19,043 19,043    
Investments, at fair value, ending balance 20,457 [2],[10],[27]     20,457 [2],[10],[27]   19,043 [1],[5],[26]
Investment, Identifier [Axis]: Symplr Software, Inc., Preferred stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     6,675 6,675    
Investments, at fair value, ending balance 7,365 [2],[10],[27]     7,365 [2],[10],[27]   6,675 [1],[5],[26]
Investment, Identifier [Axis]: Symplr Software, Inc., Preferred stock 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     2,527 2,527    
Investments, at fair value, ending balance 2,715 [2],[10],[27]     2,715 [2],[10],[27]   2,527 [1],[5],[26]
Investment, Identifier [Axis]: Symplr Software, Inc., Preferred stock 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,478 1,478    
Investments, at fair value, ending balance 1,588 [2],[10],[27]     1,588 [2],[10],[27]   1,478 [1],[5],[26]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[16]     3,668 3,668    
Investments, at fair value, ending balance 3,244 [2],[10],[15]     3,244 [2],[10],[15]   3,668 [1],[5],[14],[16]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     972 972    
Investments, at fair value, ending balance 861 [2],[10],[15]     861 [2],[10],[15]   972 [1],[5],[9],[14]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     610 610    
Investments, at fair value, ending balance 540 [2],[10],[15]     540 [2],[10],[15]   610 [1],[5],[14]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     458 458    
Investments, at fair value, ending balance 405 [2],[10],[15]     405 [2],[10],[15]   458 [1],[5],[14]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     168 168    
Investments, at fair value, ending balance 149 [2],[10],[15]     149 [2],[10],[15]   168 [1],[5],[9],[14]
Investment, Identifier [Axis]: TI Intermediate Holdings, LLC, Senior secured 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     31 31    
Investments, at fair value, ending balance 69 [2],[10],[15]     69 [2],[10],[15]   31 [1],[5],[14]
Investment, Identifier [Axis]: TIDI Legacy Products, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     3,520 3,520    
Investments, at fair value, ending balance 3,493 [2],[10]     3,493 [2],[10]   3,520 [1],[5],[9]
Investment, Identifier [Axis]: TIDI Legacy Products, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: TIDI Legacy Products, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[17],[18]     46,804 46,804    
Investments, at fair value, ending balance 46,443 [2],[10],[11]     46,443 [2],[10],[11]   46,804 [1],[9],[17],[18]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[17]     41,809 41,809    
Investments, at fair value, ending balance 41,482 [2],[10],[11]     41,482 [2],[10],[11]   41,809 [1],[5],[6],[16],[17]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     10,854 10,854    
Investments, at fair value, ending balance 10,769 [2],[10],[11]     10,769 [2],[10],[11]   10,854 [1],[5],[9]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     8,288 8,288    
Investments, at fair value, ending balance 8,224 [2],[10]     8,224 [2],[10]   8,288 [1],[5],[9]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,264 5,264    
Investments, at fair value, ending balance 5,223 [2],[10]     5,223 [2],[10]   5,264 [1],[5],[9]
Investment, Identifier [Axis]: TWAS Holdings, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Teaching Company, The, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     13,614 13,614    
Investments, at fair value, ending balance 12,167 [2],[10]     12,167 [2],[10]   13,614 [1],[5]
Investment, Identifier [Axis]: Teaching Company, The, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 38 [2],[10]     38 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Tebra Technologies, Inc., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2,972 2,972    
Investments, at fair value, ending balance 4,631 [2],[10]     4,631 [2],[10]   2,972 [1],[5]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     11,261 11,261    
Investments, at fair value, ending balance 11,559 [2],[10],[15]     11,559 [2],[10],[15]   11,261 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 10            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     88 88    
Investments, at fair value, ending balance 90 [2],[10],[15]     90 [2],[10],[15]   88 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     10,962 10,962    
Investments, at fair value, ending balance 11,252 [2],[10],[15]     11,252 [2],[10],[15]   10,962 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     7,222 7,222    
Investments, at fair value, ending balance 7,413 [2],[10],[15]     7,413 [2],[10],[15]   7,222 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,857 1,857    
Investments, at fair value, ending balance 1,906 [2],[10],[15]     1,906 [2],[10],[15]   1,857 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,651 1,651    
Investments, at fair value, ending balance 1,694 [2],[10],[15]     1,694 [2],[10],[15]   1,651 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,238 1,238    
Investments, at fair value, ending balance 1,271 [2],[10],[15]     1,271 [2],[10],[15]   1,238 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     1,031 1,031    
Investments, at fair value, ending balance 1,059 [2],[10],[15]     1,059 [2],[10],[15]   1,031 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     825 825    
Investments, at fair value, ending balance 847 [2],[10],[15]     847 [2],[10],[15]   825 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., One stop 9            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     164 164    
Investments, at fair value, ending balance 169 [2],[10],[15]     169 [2],[10],[15]   164 [1],[5],[14]
Investment, Identifier [Axis]: Tebra Technologies, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     11 11    
Investments, at fair value, ending balance 13 [2],[10]     13 [2],[10]   11 [1],[5]
Investment, Identifier [Axis]: Tebra Technologies, Inc., Warrant 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     547 547    
Investments, at fair value, ending balance 675 [2],[10]     675 [2],[10]   547 [1],[5]
Investment, Identifier [Axis]: Tebra Technologies, Inc., Warrant 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     56 56    
Investments, at fair value, ending balance 6 [2],[10]     6 [2],[10]   56 [1],[5]
Investment, Identifier [Axis]: Telesoft Holdings LLC, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     123 123    
Investments, at fair value, ending balance 133 [2],[10]     133 [2],[10]   123 [1],[5]
Investment, Identifier [Axis]: Telesoft Holdings LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16],[17],[19]     21,186 21,186    
Investments, at fair value, ending balance 21,019 [2],[10],[11],[20]     21,019 [2],[10],[11],[20]   21,186 [1],[5],[16],[17],[19]
Investment, Identifier [Axis]: Telesoft Holdings LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,432 1,432    
Investments, at fair value, ending balance 1,421 [2],[10]     1,421 [2],[10]   1,432 [1],[5],[9]
Investment, Identifier [Axis]: Telesoft Holdings LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     74 74    
Investments, at fair value, ending balance 74 [2],[10]     74 [2],[10]   74 [1],[5]
Investment, Identifier [Axis]: Templafy APS and Templafy, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[52]     4,800 4,800    
Investments, at fair value, ending balance 4,800 [2],[10],[25],[53]     4,800 [2],[10],[25],[53]   4,800 [1],[5],[8],[9],[52]
Investment, Identifier [Axis]: Templafy APS and Templafy, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[52]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[25],[53]     0 [2],[10],[25],[53]   0 [1],[5],[8],[52]
Investment, Identifier [Axis]: Templafy APS and Templafy, LLC, Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[52]     96 96    
Investments, at fair value, ending balance 43 [2],[10],[25],[53]     43 [2],[10],[25],[53]   96 [1],[5],[8],[52]
Investment, Identifier [Axis]: Thermogenics, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28],[32] 142     142    
Investment, Identifier [Axis]: Thermogenics, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[28] (1)     (1)    
Investment, Identifier [Axis]: Thermogenics, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[28] 180     180    
Investment, Identifier [Axis]: Thermogenics, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[28] (3)     (3)    
Investment, Identifier [Axis]: Titan Fitness, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[9],[14],[18]     33,063 33,063    
Investments, at fair value, ending balance 31,477 [2],[10],[15]     31,477 [2],[10],[15]   33,063 [1],[5],[6],[9],[14],[18]
Investment, Identifier [Axis]: Titan Fitness, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     2,398 2,398    
Investments, at fair value, ending balance 2,283 [2],[10],[15]     2,283 [2],[10],[15]   2,398 [1],[5],[14]
Investment, Identifier [Axis]: Titan Fitness, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     300 300    
Investments, at fair value, ending balance 318 [2],[10],[15]     318 [2],[10],[15]   300 [1],[5],[14]
Investment, Identifier [Axis]: Titan Fitness, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 12     12    
Investment, Identifier [Axis]: Togetherwork Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     27,973 27,973    
Investments, at fair value, ending balance 27,485 [2],[10],[11]     27,485 [2],[10],[11]   27,973 [1],[5],[17]
Investment, Identifier [Axis]: Togetherwork Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 649 [2],[10]     649 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Togetherwork Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (24) [2],[10],[13]     (24) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Togetherwork Holdings, LLC, Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,355 1,355    
Investments, at fair value, ending balance 1,303 [2],[10]     1,303 [2],[10]   1,355 [1],[5]
Investment, Identifier [Axis]: Transaction Data Systems, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[16],[18],[19]     75,488 75,488    
Investments, at fair value, ending balance 74,739 [2],[10],[11],[20]     74,739 [2],[10],[11],[20]   75,488 [1],[5],[6],[16],[18],[19]
Investment, Identifier [Axis]: Transaction Data Systems, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: Transform Bidco Limited, LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31] 2,349     2,349    
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     5,337 5,337    
Investments, at fair value, ending balance 5,405 [2],[10],[25],[31]     5,405 [2],[10],[25],[31]   5,337 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29]     (2) (2)    
Investments, at fair value, ending balance 4,308 [2],[10],[25],[31]     4,308 [2],[10],[25],[31]   (2) [1],[5],[8],[12],[29]
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29]     (145) (145)    
Investments, at fair value, ending balance 4,010 [2],[10],[25],[31],[32]     4,010 [2],[10],[25],[31],[32]   (145) [1],[5],[8],[12],[29]
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[31],[32] 653     653    
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] 0     0    
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] 0     0    
Investment, Identifier [Axis]: Transform Bidco Limited, One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13],[25],[31] 0     0    
Investment, Identifier [Axis]: Tricentis Operations Holdings, Inc., LP interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 42     42    
Investment, Identifier [Axis]: Tricentis Operations Holdings, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 7,646     7,646    
Investment, Identifier [Axis]: Tricentis Operations Holdings, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Tricentis Operations Holdings, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Trinity Air Consultants Holdings Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,632 2,632    
Investments, at fair value, ending balance 2,632 [2],[10]     2,632 [2],[10]   2,632 [1],[5],[9]
Investment, Identifier [Axis]: Trinity Air Consultants Holdings Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     530 530    
Investments, at fair value, ending balance 530 [2],[10]     530 [2],[10]   530 [1],[5]
Investment, Identifier [Axis]: Trinity Air Consultants Holdings Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Trinity Air Consultants Holdings Corporation, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     494 494    
Investments, at fair value, ending balance 494 [2],[10]     494 [2],[10]   494 [1],[5]
Investment, Identifier [Axis]: Trinity Air Consultants Holdings Corporation, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 249     249    
Investment, Identifier [Axis]: Triple Lift, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     7,008 7,008    
Investments, at fair value, ending balance 6,953 [2],[11],[20]     6,953 [2],[11],[20]   7,008 [1],[5],[19]
Investment, Identifier [Axis]: Triple Lift, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,495 1,495    
Investments, at fair value, ending balance 1,482 [2],[10],[11]     1,482 [2],[10],[11]   1,495 [1],[5],[9]
Investment, Identifier [Axis]: Triple Lift, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     50 50    
Investments, at fair value, ending balance (6) [2],[10],[13]     (6) [2],[10],[13]   50 [1],[5]
Investment, Identifier [Axis]: Tronair Parent, Inc., LLC units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     66 66    
Investments, at fair value, ending balance 84 [2],[10]     84 [2],[10]   66 [1],[5]
Investment, Identifier [Axis]: Ultimate Baked Goods Midco LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     9,314 9,314    
Investments, at fair value, ending balance [1],[5],[9]           9,314
Investment, Identifier [Axis]: Ultimate Baked Goods Midco LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     48 48    
Investments, at fair value, ending balance [1],[5]           48
Investment, Identifier [Axis]: Ultimate Baked Goods Midco LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,926 1,926    
Investments, at fair value, ending balance [1],[5]           1,926
Investment, Identifier [Axis]: Unchained Labs, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,372 1,372    
Investments, at fair value, ending balance 1,347 [2],[10]     1,347 [2],[10]   1,372 [1],[5]
Investment, Identifier [Axis]: Unchained Labs, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,158 1,158    
Investments, at fair value, ending balance 1,137 [2],[10]     1,137 [2],[10]   1,158 [1],[5],[9]
Investment, Identifier [Axis]: Unchained Labs, LLC, Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   (2) [1],[5],[12]
Investment, Identifier [Axis]: VSG Acquisition Corp. and Sherrill, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     47 47    
Investments, at fair value, ending balance 83 [2],[10]     83 [2],[10]   47 [1],[5]
Investment, Identifier [Axis]: VSG Acquisition Corp. and Sherrill, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     11,749 11,749    
Investments, at fair value, ending balance 12,020 [2],[10],[11]     12,020 [2],[10],[11]   11,749 [1],[5],[17]
Investment, Identifier [Axis]: VSG Acquisition Corp. and Sherrill, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,569 1,569    
Investments, at fair value, ending balance 2,079 [2],[10]     2,079 [2],[10]   1,569 [1],[5]
Investment, Identifier [Axis]: VSG Acquisition Corp. and Sherrill, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (6) (6)    
Investments, at fair value, ending balance 1,606 [2],[10]     1,606 [2],[10]   (6) [1],[5],[12]
Investment, Identifier [Axis]: VSG Acquisition Corp. and Sherrill, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 38     38    
Investment, Identifier [Axis]: Vantage Bidco GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[30],[44]     8,654 8,654    
Investments, at fair value, ending balance 9,261 [2],[10],[15],[25],[32],[45]     9,261 [2],[10],[15],[25],[32],[45]   8,654 [1],[5],[8],[9],[14],[30],[44]
Investment, Identifier [Axis]: Vantage Bidco GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[30],[44]     (11) (11)    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[32],[45]     0 [2],[10],[13],[25],[32],[45]   (11) [1],[5],[8],[12],[30],[44]
Investment, Identifier [Axis]: Varicent Intermediate Holdings Corporation, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14]     46,267 46,267    
Investments, at fair value, ending balance 50,798 [2],[10],[15],[25],[28]     50,798 [2],[10],[15],[25],[28]   46,267 [1],[5],[14]
Investment, Identifier [Axis]: Varicent Intermediate Holdings Corporation, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (93) (93)    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[28]     0 [2],[10],[13],[25],[28]   (93) [1],[5],[12]
Investment, Identifier [Axis]: Varicent Intermediate Holdings Corporation, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (90) (90)    
Investments, at fair value, ending balance 0 [2],[10],[13],[25],[28]     0 [2],[10],[13],[25],[28]   (90) [1],[5],[12]
Investment, Identifier [Axis]: Varinem German Midco GMBH, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[44]     7,299 7,299    
Investments, at fair value, ending balance 7,820 [2],[10],[25],[32],[45]     7,820 [2],[10],[25],[32],[45]   7,299 [1],[5],[8],[30],[44]
Investment, Identifier [Axis]: Varinem German Midco GMBH, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[44]     0 0    
Investments, at fair value, ending balance 4,159 [2],[10],[25],[32],[45]     4,159 [2],[10],[25],[32],[45]   0 [1],[5],[8],[30],[44]
Investment, Identifier [Axis]: Vector CS Midco Limited & Cloudsense Ltd., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[21],[29],[30]     7,004 7,004    
Investments, at fair value, ending balance [1],[5],[8],[14],[21],[29],[30]           7,004
Investment, Identifier [Axis]: Vector CS Midco Limited & Cloudsense Ltd., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[14],[21],[29],[30]     138 138    
Investments, at fair value, ending balance [1],[5],[8],[14],[21],[29],[30]           138
Investment, Identifier [Axis]: Vendavo, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[17],[18]     25,460 25,460    
Investments, at fair value, ending balance 24,720 [2],[10]     24,720 [2],[10]   25,460 [1],[5],[6],[17],[18]
Investment, Identifier [Axis]: Vendavo, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,129 1,129    
Investments, at fair value, ending balance 1,831 [2],[10]     1,831 [2],[10]   1,129 [1],[5]
Investment, Identifier [Axis]: Vendavo, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     928 928    
Investments, at fair value, ending balance 901 [2],[10]     901 [2],[10]   928 [1],[5]
Investment, Identifier [Axis]: Veranex, Inc., Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14],[21]     2,403 2,403    
Investments, at fair value, ending balance 2,531 [2],[10],[15],[22]     2,531 [2],[10],[15],[22]   2,403 [1],[5],[9],[14],[21]
Investment, Identifier [Axis]: Veranex, Inc., Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     284 284    
Investments, at fair value, ending balance 307 [2],[10],[15],[22]     307 [2],[10],[15],[22]   284 [1],[5],[14],[21]
Investment, Identifier [Axis]: Veranex, Inc., Senior secured 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[21]     72 72    
Investments, at fair value, ending balance 76 [2],[10],[15],[22]     76 [2],[10],[15],[22]   72 [1],[5],[14],[21]
Investment, Identifier [Axis]: Vermont Aus Pty Ltd, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[42]     9,465 9,465    
Investments, at fair value, ending balance 8,939 [2],[10],[25],[32],[48]     8,939 [2],[10],[25],[32],[48]   9,465 [1],[5],[8],[30],[42]
Investment, Identifier [Axis]: Vermont Aus Pty Ltd, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[30],[42]     10,081 10,081    
Investments, at fair value, ending balance 8,746 [2],[10],[25],[32],[48]     8,746 [2],[10],[25],[32],[48]   10,081 [1],[5],[8],[30],[42]
Investment, Identifier [Axis]: Vessco Midco Holdings, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     22,275 22,275    
Investments, at fair value, ending balance 22,500 [2],[11]     22,500 [2],[11]   22,275 [1],[5]
Investment, Identifier [Axis]: Vessco Midco Holdings, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,025 1,025    
Investments, at fair value, ending balance 2,925 [2],[10]     2,925 [2],[10]   1,025 [1],[5]
Investment, Identifier [Axis]: Vessco Midco Holdings, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (25) (25)    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   (25) [1],[5],[12]
Investment, Identifier [Axis]: Viper Bidco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 37,986     37,986    
Investment, Identifier [Axis]: Viper Bidco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[25],[32] 19,099     19,099    
Investment, Identifier [Axis]: Viper Bidco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Viper Bidco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Virginia Green Acquisition, LLC, LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     454 454    
Investments, at fair value, ending balance 446 [2],[10]     446 [2],[10]   454 [1],[5]
Investment, Identifier [Axis]: Virginia Green Acquisition, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,416 2,416    
Investments, at fair value, ending balance 2,398 [2],[10],[11]     2,398 [2],[10],[11]   2,416 [1],[5],[9]
Investment, Identifier [Axis]: Virginia Green Acquisition, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 672 [2],[10]     672 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: Virginia Green Acquisition, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     99 99    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   99 [1],[5]
Investment, Identifier [Axis]: W3 Co., LLC interest            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,679 1,679    
Investments, at fair value, ending balance 1,277 [2],[10]     1,277 [2],[10]   1,679 [1],[5]
Investment, Identifier [Axis]: W3 Co., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     252 252    
Investments, at fair value, ending balance 241 [2],[10]     241 [2],[10]   252 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     119 119    
Investments, at fair value, ending balance 93 [2],[10]     93 [2],[10]   119 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     82 82    
Investments, at fair value, ending balance 64 [2],[10]     64 [2],[10]   82 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     66 66    
Investments, at fair value, ending balance 53 [2],[10]     53 [2],[10]   66 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     59 59    
Investments, at fair value, ending balance 45 [2],[10]     45 [2],[10]   59 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     25 25    
Investments, at fair value, ending balance 20 [2],[10]     20 [2],[10]   25 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, LLC interest 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     2 2    
Investments, at fair value, ending balance 2 [2],[10]     2 [2],[10]   2 [1],[5]
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[17]     1,717 1,717    
Investments, at fair value, ending balance [1],[5],[14],[17]           1,717
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[17],[18]     7,804 7,804    
Investments, at fair value, ending balance 7,728 [2],[10]     7,728 [2],[10]   7,804 [1],[5],[14],[17],[18]
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,706     1,706    
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[17]     1,194 1,194    
Investments, at fair value, ending balance 1,185 [2],[10]     1,185 [2],[10]   1,194 [1],[5],[14],[17]
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[17]     628 628    
Investments, at fair value, ending balance 628 [2],[10]     628 [2],[10]   628 [1],[5],[14],[17]
Investment, Identifier [Axis]: WBZ Investment, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: WPEngine, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     5,438 5,438    
Investments, at fair value, ending balance 5,438 [2],[10]     5,438 [2],[10]   5,438 [1],[5],[9]
Investment, Identifier [Axis]: WPEngine, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5]
Investment, Identifier [Axis]: WRE Holding Corp., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     16,514 16,514    
Investments, at fair value, ending balance 16,390 [2],[11]     16,390 [2],[11]   16,514 [1],[5]
Investment, Identifier [Axis]: WRE Holding Corp., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     241 241    
Investments, at fair value, ending balance 295 [2],[10]     295 [2],[10]   241 [1],[5]
Investment, Identifier [Axis]: WRE Holding Corp., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10],[13]     0 [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: WRE Holding Corp., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,799     1,799    
Investment, Identifier [Axis]: WRE Holding Corp., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 1,084     1,084    
Investment, Identifier [Axis]: WRE Holding Corp., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 843     843    
Investment, Identifier [Axis]: WU Holdco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[16]     4,849 4,849    
Investments, at fair value, ending balance 9,516 [2],[10]     9,516 [2],[10]   4,849 [1],[5],[16]
Investment, Identifier [Axis]: WU Holdco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,713 1,713    
Investments, at fair value, ending balance (4) [2],[10],[13]     (4) [2],[10],[13]   1,713 [1],[5],[9]
Investment, Identifier [Axis]: WU Holdco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     446 446    
Investments, at fair value, ending balance (12) [2],[10],[13]     (12) [2],[10],[13]   446 [1],[5]
Investment, Identifier [Axis]: WU Holdco, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,567 1,567    
Investments, at fair value, ending balance [1],[5]           1,567
Investment, Identifier [Axis]: WU Holdco, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     61 61    
Investments, at fair value, ending balance [1],[5]           61
Investment, Identifier [Axis]: Wasabi Lower Holdco, LLC, Senior secured 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (9)     (9)    
Investment, Identifier [Axis]: Wasabi Lower Holdco, LLC, Senior secured 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,575     2,575    
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     3,072 3,072    
Investments, at fair value, ending balance [1],[5],[19]           3,072
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     297 297    
Investments, at fair value, ending balance [1],[5]           297
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     111 111    
Investments, at fair value, ending balance [1],[5]           111
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     742 742    
Investments, at fair value, ending balance [1],[5],[9]           742
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     371 371    
Investments, at fair value, ending balance [1],[5]           371
Investment, Identifier [Axis]: Watermill Express, LLC, One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     564 564    
Investments, at fair value, ending balance [1],[5]           564
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[11],[20] 3,027     3,027    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 293     293    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 79     79    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 731     731    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 366     366    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 6            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,366     2,366    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 7            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,754     2,754    
Investment, Identifier [Axis]: Watermill Express, LLC., One stop 8            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (12)     (12)    
Investment, Identifier [Axis]: Wealth Enhancement Group, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 3,967     3,967    
Investment, Identifier [Axis]: Wealth Enhancement Group, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 2,860     2,860    
Investment, Identifier [Axis]: Wealth Enhancement Group, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Wealth Enhancement Group, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 906     906    
Investment, Identifier [Axis]: WebPT, Inc., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     903 903    
Investments, at fair value, ending balance 873 [2],[10]     873 [2],[10]   903 [1],[5]
Investment, Identifier [Axis]: Whitebridge Pet Brands, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[6],[17],[18]     26,358 26,358    
Investments, at fair value, ending balance [1],[5],[6],[17],[18]           26,358
Investment, Identifier [Axis]: Whitebridge Pet Brands, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Wildcat TopCo, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 563     563    
Investment, Identifier [Axis]: Wildcat TopCo, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 23,361     23,361    
Investment, Identifier [Axis]: Wildcat TopCo, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 335     335    
Investment, Identifier [Axis]: Wildcat TopCo, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: Winebow Holdings, Inc., One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[9],[16]     8,887 8,887    
Investments, at fair value, ending balance 8,049 [2],[10],[11]     8,049 [2],[10],[11]   8,887 [1],[9],[16]
Investment, Identifier [Axis]: Wineshipping.com LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[17]     9,190 9,190    
Investments, at fair value, ending balance (235) [2],[10],[13]     (235) [2],[10],[13]   9,190 [1],[5],[17]
Investment, Identifier [Axis]: Wineshipping.com LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     251 251    
Investments, at fair value, ending balance 8,277 [2],[10],[15]     8,277 [2],[10],[15]   251 [1],[5]
Investment, Identifier [Axis]: Wineshipping.com LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     138 138    
Investments, at fair value, ending balance 223 [2],[10],[15]     223 [2],[10],[15]   138 [1],[5]
Investment, Identifier [Axis]: Wineshipping.com LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[15] 138     138    
Investment, Identifier [Axis]: Wizard Bidco Limited, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[29]     22,740 22,740    
Investments, at fair value, ending balance 22,740 [2],[10],[25],[31]     22,740 [2],[10],[25],[31]   22,740 [1],[5],[8],[9],[29]
Investment, Identifier [Axis]: Wizard Bidco Limited, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[9],[14],[29],[30]     10,483 10,483    
Investments, at fair value, ending balance 11,396 [2],[10],[15],[25],[31],[32]     11,396 [2],[10],[15],[25],[31],[32]   10,483 [1],[5],[8],[9],[14],[29],[30]
Investment, Identifier [Axis]: Wizard Bidco Limited, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     8,322 8,322    
Investments, at fair value, ending balance 8,544 [2],[10],[25],[31],[32]     8,544 [2],[10],[25],[31],[32]   8,322 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Wizard Bidco Limited, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[29],[30]     192 192    
Investments, at fair value, ending balance 178 [2],[10],[25],[31],[32]     178 [2],[10],[25],[31],[32]   192 [1],[5],[8],[29],[30]
Investment, Identifier [Axis]: Wizard Bidco Limited, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[8],[12],[29],[30]     0 0    
Investments, at fair value, ending balance [1],[5],[8],[12],[29],[30]           0
Investment, Identifier [Axis]: Workforce Software, LLC, Common stock 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[26]     1,524 1,524    
Investments, at fair value, ending balance [1],[5],[26]           1,524
Investment, Identifier [Axis]: Workforce Software, LLC, Common stock 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     48 48    
Investments, at fair value, ending balance [1],[5]           48
Investment, Identifier [Axis]: Workforce Software, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     41,999 41,999    
Investments, at fair value, ending balance [1],[5],[14],[19]           41,999
Investment, Identifier [Axis]: Workforce Software, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[14],[19]     7,436 7,436    
Investments, at fair value, ending balance [1],[5],[14],[19]           7,436
Investment, Identifier [Axis]: Workforce Software, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     5,266 5,266    
Investments, at fair value, ending balance [1],[5],[9],[14]           5,266
Investment, Identifier [Axis]: Workforce Software, LLC, One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[14]     1,580 1,580    
Investments, at fair value, ending balance [1],[5],[9],[14]           1,580
Investment, Identifier [Axis]: Workforce Software, LLC, One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: World Insurance Associates, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: World Insurance Associates, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] 0     0    
Investment, Identifier [Axis]: YE Brands Holding, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9],[16]     17,632 17,632    
Investments, at fair value, ending balance 17,498 [2],[10],[11]     17,498 [2],[10],[11]   17,632 [1],[5],[9],[16]
Investment, Identifier [Axis]: YE Brands Holding, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     933 933    
Investments, at fair value, ending balance 1,101 [2],[10]     1,101 [2],[10]   933 [1],[5]
Investment, Identifier [Axis]: YE Brands Holding, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     54 54    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   54 [1],[5]
Investment, Identifier [Axis]: YI, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     4,430 4,430    
Investments, at fair value, ending balance 4,353 [2],[10]     4,353 [2],[10]   4,430 [1],[5],[9]
Investment, Identifier [Axis]: YI, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance (2) [2],[10],[13]     (2) [2],[10],[13]   0 [1],[5],[12]
Investment, Identifier [Axis]: YI, LLC, One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance [1],[5],[12]           0
Investment, Identifier [Axis]: Yorkshire Parent, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     577 577    
Investments, at fair value, ending balance 577 [2],[10]     577 [2],[10]   577 [1],[5]
Investment, Identifier [Axis]: Yorkshire Parent, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     2,634 2,634    
Investments, at fair value, ending balance 2,253 [2],[10]     2,253 [2],[10]   2,634 [1],[5],[9]
Investment, Identifier [Axis]: Yorkshire Parent, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 72 [2],[10]     72 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Yorkshire Parent, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 2,234 [2],[10]     2,234 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Yorkshire Parent, Inc., One stop 4            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 619     619    
Investment, Identifier [Axis]: Yorkshire Parent, Inc., One stop 5            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 62     62    
Investment, Identifier [Axis]: Zarya Holdco, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     1,385 1,385    
Investments, at fair value, ending balance 7,193 [2],[10]     7,193 [2],[10]   1,385 [1],[5],[9]
Investment, Identifier [Axis]: Zarya Holdco, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     7,102 7,102    
Investments, at fair value, ending balance 1,403 [2],[10]     1,403 [2],[10]   7,102 [1],[5],[9]
Investment, Identifier [Axis]: Zarya Holdco, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     (2) (2)    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   (2) [1],[5],[12]
Investment, Identifier [Axis]: Zendesk, Inc., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     602 602    
Investments, at fair value, ending balance 627 [2],[10]     627 [2],[10]   602 [1],[5]
Investment, Identifier [Axis]: Zendesk, Inc., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[19]     28,647 28,647    
Investments, at fair value, ending balance 28,438 [2],[10],[20]     28,438 [2],[10],[20]   28,647 [1],[5],[19]
Investment, Identifier [Axis]: Zendesk, Inc., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 2,185 [2],[10]     2,185 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Zendesk, Inc., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[12]     0 0    
Investments, at fair value, ending balance 0 [2],[10]     0 [2],[10]   0 [1],[5],[12]
Investment, Identifier [Axis]: Zullas, L.C., LP units            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 250     250    
Investment, Identifier [Axis]: Zullas, L.C., One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (1)     (1)    
Investment, Identifier [Axis]: Zullas, L.C., One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 438     438    
Investment, Identifier [Axis]: Zullas, L.C., One stop 3            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10],[13] (2)     (2)    
Investment, Identifier [Axis]: bswift, LLC, One stop            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5],[9]     7,817 7,817    
Investments, at fair value, ending balance [1],[5],[9]           7,817
Investment, Identifier [Axis]: bswift, LLC, One stop 1            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] 7,623     7,623    
Investment, Identifier [Axis]: bswift, LLC, One stop 2            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, ending balance [2],[10] $ 9,975     9,975    
Investment, Identifier [Axis]: mParticle, Inc., Preferred stock            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     1,120 1,120    
Investments, at fair value, ending balance [1],[5]           1,120
Investment, Identifier [Axis]: mParticle, Inc., Warrant            
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]            
Investments, at fair value, beginning balance [1],[5]     $ 382 $ 382    
Investments, at fair value, ending balance [1],[5]           $ 382
Fair Value | Asset Concentration Risk | Non-qualifying Asset            
Concentration risk, percentage     13.30% 15.70%    
[1] The fair values of investments were valued using significant unobservable inputs, unless noted otherwise. See Note 6.
[2] The fair values of investments were valued using significant unobservable inputs, unless noted otherwise. See Note 6.
[3] As defined in the 1940 Act, the Company is deemed to be an “affiliated person” of the portfolio company as the Company owns five percent or more of the portfolio company's voting securities (“non-controlled affiliate”). Transactions related to investments in non-controlled affiliates for the year ended September 30, 2024 were as follows:
Portfolio CompanyFair value as of September 30, 2023
Gross additions(a)
Gross reductions(b)
Net change in unrealized appreciation (depreciation)Net realized gain (loss)Fair value as of September 30, 2024Interest, dividend and fee income
Abita Brewing Co. LLC$6,536 $2,166 $(709)$(1,993)$— $6,000 $575 
Bayside Opco, LLC22,044 2,758 (699)5,024 — 29,127 3,660 
Benetech, Inc.1,353 780 (843)503 — 1,793 9 
Elite Dental Partners LLC13,396 5,845 (3,013)(4,532)— 11,696 180 
Imperial Optical Midco Inc.— 94,556 — (692)— 93,864 1,008 
Opening Day Borrower 111 LLC24,438 27,853 (23,040)(4,272)(43)24,936 629 
Rubio's Restaurants, Inc.12,063 3,759 (3,929)6,624 (18,517)— 1,187 
SPF Borrower LLC— 34,008 (136)2,781 — 36,653 2,112 
Switchfly LLC7,254 6,180 (5,378)1,157 (1,900)7,313 88 
Total Non-Controlled Affiliates$87,084 $177,905 $(37,747)$4,600 $(20,460)$211,382 $9,448 
(a)
Gross additions could include increases in the cost basis of investments resulting from new investments, amounts related to PIK interest capitalized and added to the principal balance of the respective loans, the accretion of discounts, the exchange of one or more existing investments for one or more new investments and the movement of an existing portfolio company into this affiliated category from a different category.
(b)
Gross reductions could include decreases in the cost basis of investments resulting from principal collections related to investment repayments and sales, the amortization of premiums, the reversal of capitalized PIK for non-accrual positions and the exchange of one or more existing securities for one or more new securities.
[4] As defined in the 1940 Act, the Company is deemed to be both an “affiliated person” of and “control” this portfolio company as the Company owns more than 25% of the portfolio company's outstanding voting securities or has the power to exercise control over management or policies of such portfolio company (including through a management agreement) (“controlled affiliate”). Transactions related to investments in controlled affiliates for the nine months ended June 30, 2025 were as follows:
Portfolio CompanyFair value as of September 30, 2024
Gross additions(a)
Gross reductions(b)
Net change in unrealized appreciation (depreciation)Net realized gain (loss)Fair value as of June 30, 2025Interest, dividend and fee income
MMan Acquisition Co.$12,205 $362 $— $(711)$— $11,856 $377 
Total Controlled Affiliates$12,205 $362 $— $(711)$— $11,856 $377 
(a)
Gross additions could include increases in the cost basis of investments resulting from new investments, amounts related to PIK interest capitalized and added to the principal balance of the respective loans, the accretion of discounts, the exchange of one or more existing investments for one or more new investments and the movement of an existing portfolio company into this affiliated category from a different category.
(b)
Gross reductions could include decreases in the cost basis of investments resulting from principal collections related to investment repayments or sales, the amortization of premiums, the reversal of capitalized PIK for non-accrual positions and the exchange of one or more existing securities for one or more new securities.
[5]
Denotes that all or a portion of the investment collateralizes the JPM Credit Facility (as defined in Note 7).
[6]
Denotes that all or a portion of the loan secures the notes offered in the 2018 Debt Securitization (as defined in Note 7).
[7] The headquarters of this portfolio company is located in Canada.
[8] The investment is treated as a non-qualifying asset under Section 55(a) of the Investment Company Act of 1940, as amended (the “1940 Act”). Under the 1940 Act, the Company cannot acquire any non-qualifying asset unless, at the time the acquisition is made, qualifying assets represent at least 70% of the Company's total assets. As of September 30, 2024, total non-qualifying assets at fair value represented 13.3% of the Company's total assets calculated in accordance with the 1940 Act.
[9]
Denotes that all or a portion of the loan collateralizes the GBDC 3 DB Credit Facility (as defined in Note 7).
[10]
Denotes that all or a portion of the investment collateralizes the JPM Credit Facility (as defined in Note 7).
[11]
Denotes that all or a portion of the loan collateralizes the notes offered in the 2024 Debt Securitization (as defined in Note 7).
[12] The negative fair value is the result of the capitalized discount on the loan or the unfunded commitment being valued below par. The negative amortized cost is the result of the capitalized discount being greater than the principal amount outstanding on the loan.
[13] The negative fair value is the result of the capitalized discount on the loan or the unfunded commitment being valued below par. The negative amortized cost is the result of the capitalized discount being greater than the principal amount outstanding on the loan.
[14] All or a portion of the loan interest was capitalized into the outstanding principal balance of the loan in accordance with the terms of the credit agreement during the year ended September 30, 2024.
[15] All or a portion of the loan interest was capitalized into the outstanding principal balance of the loan in accordance with the terms of the credit agreement during the nine months ended June 30, 2025.
[16]
Denotes that all or a portion of the loan secures the notes offered in the GBDC 3 2021 Debt Securitization (as defined in Note 7).
[17]
Denotes that all or a portion of the loan secures the notes offered in the GBDC 3 2022-2 Debt Securitization (as defined in Note 7).
[18]
Denotes that all or a portion of the loan secures the notes offered in the GCIC 2018 Debt Securitization (as defined in Note 7).
[19]
Denotes that all or a portion of the loan secures the notes offered in the GBDC 3 2022 Debt Securitization (as defined in Note 7).
[20]
Denotes that all or a portion of the loan secures the notes offered in the GBDC 3 2022 Debt Securitization (as defined in Note 7).
[21] Loan was on non-accrual status as of September 30, 2024, meaning that the Company has ceased recognizing interest income on the loan.
[22] Investment was on non-accrual status as of June 30, 2025, meaning that the Company has ceased recognizing interest or non-cash dividend income on the investment.
[23] The headquarters of this portfolio company is located in Luxembourg.
[24] The headquarters of this portfolio company is located in Spain.
[25] The investment is treated as a non-qualifying asset under Section 55(a) of the Investment Company Act of 1940, as amended (the “1940 Act”). Under the 1940 Act, the Company cannot acquire any non-qualifying asset unless, at the time the acquisition is made, qualifying assets represent at least 70% of the Company's total assets. As of June 30, 2025, total non-qualifying assets at fair value represented 15.7% of the Company's total assets calculated in accordance with the 1940 Act.
[26] The Company holds an equity investment that is income producing.
[27] The Company holds an equity investment that is income producing.
[28] The headquarters of this portfolio company is located in Canada.
[29] The headquarters of this portfolio company is located in the United Kingdom.
[30] Investment is denominated in foreign currency and is translated into U.S. dollars as of the valuation date or the date of the transaction. See Note 2.
[31] The headquarters of this portfolio company is located in the United Kingdom.
[32] Investment is denominated in foreign currency and is translated into U.S. dollars as of the valuation date or the date of the transaction. See Note 2.
[33] The headquarters of this portfolio company is located in Netherlands.
[34] The headquarters of this portfolio company is located in Netherlands.
[35] The headquarters of this portfolio company is located in France.
[36] The headquarters of this portfolio company is located in France.
[37] The fair value of the loan reflects the legal claim on par and accrued uncapitalized payment-in-kind (“PIK”) interest.
[38] The fair value of the loan reflects the legal claim on par and accrued uncapitalized payment-in-kind (“PIK”) interest.
[39] The headquarters of this portfolio company is located in Luxembourg.
[40] The headquarters of this portfolio company is located in Israel.
[41] The headquarters of this portfolio company is located in Israel.
[42] The headquarters of this portfolio company is located in Australia.
[43] The fair value of this investment was valued using Level 1 inputs. See Note 6.
[44] The headquarters of this portfolio company is located in Germany.
[45] The headquarters of this portfolio company is located in Germany.
[46] The headquarters of this portfolio company is located in Sweden.
[47] The headquarters of this portfolio company is located in Sweden.
[48] The headquarters of this portfolio company is located in Australia.
[49] The headquarters of this portfolio company is located in Jersey.
[50] The headquarters of this portfolio company is located in Finland.
[51] The headquarters of this portfolio company is located in Finland.
[52] The headquarters of this portfolio company is located in Denmark.
[53] The headquarters of this portfolio company is located in Denmark.