v3.26.1
Fair Value - Summary of Changes in Fair Value of Level 3 Assets (Detail) - Investments [Member] - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Beginning balance $ 85,760 $ 70,320
Total gains or losses included in earnings:    
Purchase of investment securities 15,955 [1] 11,227 [2]
Proceeds from dispositions of investment securities (7,104) (7,956)
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Closing balance 94,090 73,400
Unrealized gains (losses) for the period relating to those Level 3 assets that were still held by the Company at the end of the period:    
Net change in unrealized gain (loss) (521) 21
Realized Investment Gains Losses [Member]    
Total gains or losses included in earnings:    
Net realized gain 0 0
Unrealized Gain Loss On Investments [Member]    
Total gains or losses included in earnings:    
Net realized gain (521) (191)
Bank Debt/Senior Secured Loans [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Beginning balance 82,835 67,638
Total gains or losses included in earnings:    
Purchase of investment securities 15,880 [1] 11,158 [2]
Proceeds from dispositions of investment securities (7,104) (7,956)
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Closing balance 91,100 70,660
Unrealized gains (losses) for the period relating to those Level 3 assets that were still held by the Company at the end of the period:    
Net change in unrealized gain (loss) (511) 32
Bank Debt/Senior Secured Loans [Member] | Realized Investment Gains Losses [Member]    
Total gains or losses included in earnings:    
Net realized gain 0 0
Bank Debt/Senior Secured Loans [Member] | Unrealized Gain Loss On Investments [Member]    
Total gains or losses included in earnings:    
Net realized gain (511) (180)
Preferred Equity [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Beginning balance 2,866 2,622
Total gains or losses included in earnings:    
Purchase of investment securities 75 [1] 69 [2]
Proceeds from dispositions of investment securities 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Closing balance 2,930 2,681
Unrealized gains (losses) for the period relating to those Level 3 assets that were still held by the Company at the end of the period:    
Net change in unrealized gain (loss) (11) (10)
Preferred Equity [Member] | Realized Investment Gains Losses [Member]    
Total gains or losses included in earnings:    
Net realized gain 0 0
Preferred Equity [Member] | Unrealized Gain Loss On Investments [Member]    
Total gains or losses included in earnings:    
Net realized gain (11) (10)
Common Equity/Warrants [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Beginning balance 59 60
Total gains or losses included in earnings:    
Purchase of investment securities 0 [1] 0 [2]
Proceeds from dispositions of investment securities 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Closing balance 60 59
Unrealized gains (losses) for the period relating to those Level 3 assets that were still held by the Company at the end of the period:    
Net change in unrealized gain (loss) 1 (1)
Common Equity/Warrants [Member] | Realized Investment Gains Losses [Member]    
Total gains or losses included in earnings:    
Net realized gain 0 0
Common Equity/Warrants [Member] | Unrealized Gain Loss On Investments [Member]    
Total gains or losses included in earnings:    
Net realized gain $ 1 $ (1)
[1] Includes PIK capitalization and accretion of discount.
[2] Includes PIK capitalization and accretion of discount.