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Fair Value Measurements - Summary of Reconciliation of Beginning and Ending Balances for Fair Valued Investments (Details) - Level 3 - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax
Net change in unrealized appreciation (depreciation) on investments | $ (521) | $ (2,861) | $ (6,578) | $ 1,099
Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | $ 1,090,506 | $ 957,649
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  |  | Realized Gain (Loss), Investment and Derivative, Operating, before Tax | Realized Gain (Loss), Investment and Derivative, Operating, before Tax
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  |  | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax | Unrealized Gain (Loss), Investment and Derivative, Operating, before Tax
Net realized gains (losses) on investments |  |  | $ 4,832 | $ 12,161
Net change in unrealized appreciation (depreciation) on investments |  |  | 8,009 | (5,149)
Purchase of investments |  |  | 284,480 | 274,194
Proceeds from sales and repayments of investments |  |  | (203,319) | (154,109)
Interest and dividend income paid-in-kind |  |  | 7,884 | 5,745
Proceeds from loan origination fees |  |  | (1,757) | (1,952)
Accretion of loan origination fees |  |  | 2,007 | 1,801
Accretion of original issue discount |  |  | 106 | 335
Ending Balance | 1,192,748 | 1,090,675 | 1,192,748 | 1,090,675
Subordinated Debt | Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | 142,839 | 135,173
Net change in unrealized appreciation (depreciation) on investments |  |  | (470) | 1,256
Purchase of investments |  |  |  | 12,500
Proceeds from sales and repayments of investments |  |  | (37,246) | (2,864)
Interest and dividend income paid-in-kind |  |  | 2,378 | 3,101
Proceeds from loan origination fees |  |  |  | (157)
Accretion of loan origination fees |  |  | 199 | 156
Accretion of original issue discount |  |  | 5 | 5
Ending Balance | 107,705 | 149,170 | 107,705 | 149,170
First Lien Debt | Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | 718,120 | 578,140
Net realized gains (losses) on investments |  |  | (14,498) | (3,280)
Net change in unrealized appreciation (depreciation) on investments |  |  | 23,929 | (1,467)
Purchase of investments |  |  | 256,210 | 212,495
Proceeds from sales and repayments of investments |  |  | (137,539) | (90,314)
Interest and dividend income paid-in-kind |  |  | 3,348 | 822
Proceeds from loan origination fees |  |  | (1,667) | (1,672)
Accretion of loan origination fees |  |  | 1,726 | 1,503
Accretion of original issue discount |  |  | 101 | 53
Transfers by type |  |  | 9,645 |
Ending Balance | 859,375 | 696,280 | 859,375 | 696,280
Second Lien Debt | Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | 83,543 | 119,561
Net realized gains (losses) on investments |  |  |  | (2,100)
Net change in unrealized appreciation (depreciation) on investments |  |  | (7,381) | (2,481)
Purchase of investments |  |  | 13,600 | 33,281
Proceeds from sales and repayments of investments |  |  |  | (36,472)
Interest and dividend income paid-in-kind |  |  | 2,158 | 1,822
Proceeds from loan origination fees |  |  | (90) | (123)
Accretion of loan origination fees |  |  | 82 | 142
Accretion of original issue discount |  |  |  | 277
Transfers by type |  |  | (9,645) |
Ending Balance | 82,267 | 113,907 | 82,267 | 113,907
Equity | Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | 138,371 | 120,007
Net realized gains (losses) on investments |  |  | 11,214 | 17,541
Net change in unrealized appreciation (depreciation) on investments |  |  | (2,876) | (5,524)
Purchase of investments |  |  | 14,545 | 15,918
Proceeds from sales and repayments of investments |  |  | (18,160) | (24,458)
Ending Balance | 143,094 | 123,484 | 143,094 | 123,484
Warrant | Fair Value, Recurring |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance |  |  | 7,633 | 4,768
Net realized gains (losses) on investments |  |  | 8,116 |
Net change in unrealized appreciation (depreciation) on investments |  |  | (5,193) | 3,067
Purchase of investments |  |  | 125 |
Proceeds from sales and repayments of investments |  |  | (10,374) | (1)
Ending Balance | $ 307 | $ 7,834 | $ 307 | $ 7,834

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