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Fair Value Measurements - Summary of Reconciliation of Beginning and Ending Balances for Fair Valued Investments (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Realized gain (loss) on investment | Realized gain (loss) on investment
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Realized gain (loss) on investment | Realized gain (loss) on investment
Level 3 |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Net change in unrealized appreciation (depreciation) on investments | $ (6,416) | $ 2,840
Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 1,090,506 | 957,649
Net realized gains (losses) on investments | 13,330 | 1,743
Net change in unrealized appreciation (depreciation) on investments | (9,793) | 1,222
Purchase of investments | 115,555 | 145,861
Proceeds from sales and repayments of investments | (57,343) | (60,247)
Interest and dividend income paid-in-kind | 2,239 | 2,049
Proceeds from loan origination fees | (677) | (1,131)
Accretion of loan origination fees | 548 | 556
Accretion of original issue discount | 43 | 116
Ending Balance | 1,154,408 | 1,047,818
Subordinated Debt | Level 3 | 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 | (158) | (75)
Purchase of investments | 3 | 12,500
Proceeds from sales and repayments of investments | (16,690) | (209)
Interest and dividend income paid-in-kind | 824 | 1,102
Proceeds from loan origination fees |  | (156)
Accretion of loan origination fees | 112 | 50
Accretion of original issue discount | 2 | 2
Ending Balance | 126,932 | 148,387
First Lien Debt | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 718,120 | 578,140
Net change in unrealized appreciation (depreciation) on investments | 1,180 | 1,116
Purchase of investments | 104,846 | 96,142
Proceeds from sales and repayments of investments | (23,729) | (41,963)
Interest and dividend income paid-in-kind | 700 | 256
Proceeds from loan origination fees | (621) | (896)
Accretion of loan origination fees | 409 | 478
Accretion of original issue discount | 19 | 17
Ending Balance | 800,924 | 633,290
Second Lien Debt | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 83,543 | 119,561
Net change in unrealized appreciation (depreciation) on investments | (2,203) | 453
Purchase of investments | 6,746 | 28,850
Proceeds from sales and repayments of investments |  | (14,852)
Interest and dividend income paid-in-kind | 715 | 691
Proceeds from loan origination fees | (56) | (79)
Accretion of loan origination fees | 27 | 28
Accretion of original issue discount | 22 | 97
Ending Balance | 88,794 | 134,749
Equity | Level 3 | 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 | 6,131 | 1,743
Net change in unrealized appreciation (depreciation) on investments | (3,523) | (1,456)
Purchase of investments | 3,960 | 8,369
Proceeds from sales and repayments of investments | (7,468) | (3,222)
Ending Balance | 137,471 | 125,441
Warrant | Level 3 | 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 | 7,199 |
Net change in unrealized appreciation (depreciation) on investments | (5,089) | 1,184
Proceeds from sales and repayments of investments | (9,456) | (1)
Ending Balance | $ 287 | $ 5,951

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