v3.26.1
Investments - Schedule of Transactions with Affiliated Investments and Controlled Investments (Details) - USD ($)
 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] $ 35,381,405 $ 14,750,785
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 3,408,970 (235,600)
Transfers In/(Out) of Controlled [1],[2]
Unrealized Gain/(Loss) [1],[2] (2,110,960) 7,397,502
Realized Gain/(Loss) [1],[2] 3,162 (10,320,353)
Fair value as of ending [1],[2] 36,682,577 11,592,334
Earned Income [1],[2] 2,918,091 254,231
Fee/Other Income [1],[2]
Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 121,610,914 70,931,647
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 5,456,499 53,416,033
Transfers In/(Out) of Controlled [1],[2]
Unrealized Gain/(Loss) [1],[2] 1,468,108 (892,789)
Realized Gain/(Loss) [1],[2]
Fair value as of ending [1],[2] 128,535,521 123,454,891
Earned Income [1],[2] 5,142,125 5,419,936
Fee/Other Income [1],[2] 493,787 552,882
Advocates for Disabled Vets, LLC (dba Reps for Vets) [Member] | Senior Secured First Lien Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 8,798,513  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 38,896  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (593,472)  
Realized Gain/(Loss) [1],[2] 1,696  
Fair value as of ending [1],[2] 8,245,633  
Earned Income [1],[2] 857,174  
Fee/Other Income [1],[2]  
Advocates for Disabled Vets, LLC (dba Reps for Vets) [Member] | Equity [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 3,359,511  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (960,622)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 2,398,889  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
Advocates for Disabled Vets, LLC (dba Reps for Vets) [Member] | Senior Secured Delayed Draw Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 225,132  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (3,507)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 221,625  
Earned Income [1],[2] 5,437  
Fee/Other Income [1],[2]  
Advocates for Disabled Vets, LLC (dba Reps for Vets) [Member] | Preferred Equity [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 99,396  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 99,396  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
FST Holdings Parent, LLC [Member] | Equity [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 10,960,741  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] 1,995,867  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 12,956,608  
Earned Income [1],[2] 268,540  
Fee/Other Income [1],[2]  
MB Precision Investment Holdings LLC [Member] | Senior Secured First Lien Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 6,398,561  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] (24,450)  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (251,879)  
Realized Gain/(Loss) [1],[2] 1,466  
Fair value as of ending [1],[2] 6,123,698  
Earned Income [1],[2] 660,589  
Fee/Other Income [1],[2]  
MB Precision Investment Holdings LLC [Member] | Equity [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 2,725,408  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 656,543  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (1,374,470)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 2,007,481  
Earned Income [1],[2] 656,543  
Fee/Other Income [1],[2]  
MB Precision Investment Holdings LLC [Member] | Senior Secured Delayed Draw Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 490,306  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 2,310,678  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (159,866)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 2,641,118  
Earned Income [1],[2] 204,934  
Fee/Other Income [1],[2]  
MB Precision Investment Holdings LLC [Member] | Senior Secured First Lien Revolver [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 1,975,347  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 102,775  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (89,993)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 1,988,129  
Earned Income [1],[2] 264,874  
Fee/Other Income [1],[2]  
MB Precision Investment Holdings LLC [Member] | Warrants [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 673,018  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] (673,018)  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2]  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
ECC Capital Corp [Member] | Senior Secured First Lien Term Loan [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 6,997,012 7,422,012
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]
Transfers In/(Out) of Controlled [1],[2]
Unrealized Gain/(Loss) [1],[2]
Realized Gain/(Loss) [1],[2]
Fair value as of ending [1],[2] 6,997,012 7,422,012
Earned Income [1],[2] 480,427 538,943
Fee/Other Income [1],[2]
ECC Capital Corp [Member] | Equity [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 6,636,000  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] 924,000  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 7,560,000  
Earned Income [1],[2]  
Fee/Other Income [1],[2] 118,787  
ECC Capital Corp [Member] | Equity [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   4,872,000
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   1,596,000
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2]   6,468,000
Earned Income [1],[2]  
Fee/Other Income [1],[2]   161,611
FlexFIN, LLC [Member] | Equity Interest [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 37,180,761  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] (2,617,801)  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] 745,800  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 35,308,760  
Earned Income [1],[2] 3,298,977  
Fee/Other Income [1],[2]  
NSG Captive, Inc. [Member] | Equity [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 48,469,540  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 6,474,300  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2] 3,572,078  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 58,515,918  
Earned Income [1],[2]  
Fee/Other Income [1],[2] 375,000  
NSG Captive, Inc. [Member] | Equity [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   101,000
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]   49,154,076
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   (826,575)
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2]   48,428,501
Earned Income [1],[2]  
Fee/Other Income [1],[2]   391,271
NVTN LLC [Member] | Senior Secured First Lien Delayed Draw Term Loan [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 8,900,000 5,500,000
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 950,000 4,700,000
Transfers In/(Out) of Controlled [1],[2]
Unrealized Gain/(Loss) [1],[2]
Realized Gain/(Loss) [1],[2]
Fair value as of ending [1],[2] 9,850,000 10,200,000
Earned Income [1],[2] 837,394 575,494
Fee/Other Income [1],[2]
NVTN LLC [Member] | Senior Secured First Lien Term Loan B [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2] 13,427,601 16,353,590
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]
Transfers In/(Out) of Controlled [1],[2]
Unrealized Gain/(Loss) [1],[2] (3,773,770) (1,662,214)
Realized Gain/(Loss) [1],[2]
Fair value as of ending [1],[2] 9,653,831 14,691,376
Earned Income [1],[2] 495,203 708,477
Fee/Other Income [1],[2]
NVTN LLC [Member] | Senior Secured Revolving Note [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2] 650,000  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2] 650,000  
Earned Income [1],[2] 30,124  
Fee/Other Income [1],[2]  
Black Angus Steakhouses, LLC [Member] | Senior Secured First Lien Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]  
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   7,767,533
Realized Gain/(Loss) [1],[2]   (7,767,533)
Fair value as of ending [1],[2]  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
Black Angus Steakhouses, LLC [Member] | Senior Secured First Lien Delayed Draw Term Loan [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   751,207
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]   (243,889)
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   124,542
Realized Gain/(Loss) [1],[2]   (631,860)
Fair value as of ending [1],[2]  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
Black Angus Steakhouses, LLC [Member] | Senior Secured First Lien Super Priority DDTL [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   1,647,776
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]  
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   273,184
Realized Gain/(Loss) [1],[2]   (1,920,960)
Fair value as of ending [1],[2]  
Earned Income [1],[2]  
Fee/Other Income [1],[2]  
FST Holdings Parent, LLC [Member] | Equity [Member] | Affiliated Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   12,351,802
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]   8,289
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]   (767,757)
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2]   11,592,334
Earned Income [1],[2]   254,231
Fee/Other Income [1],[2]  
FlexFIN, LLC [Member] | Equity Interest [Member] | Controlled Investments [Member]    
Affiliated Investments    
Fair value as of beginning [1],[2]   36,683,045
Purchases/(Sales) of or Advances/ (Distributions) [1],[2]   (438,043)
Transfers In/(Out) of Controlled [1],[2]  
Unrealized Gain/(Loss) [1],[2]  
Realized Gain/(Loss) [1],[2]  
Fair value as of ending [1],[2]   36,245,002
Earned Income [1],[2]   3,597,022
Fee/Other Income [1],[2]  
[1] The par amount and additional detail are shown in the Consolidated Schedules of Investments.
[2] Securities with a zero value at the beginning and end of the period, and those that had no transaction activity were excluded from the roll forward.