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Fair Value Measurements - Summary of Reconciliation of Beginning and Ending Balances for Fair Valued Investments (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
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 on investments | Realized gain on investments
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Realized gain on investments | Realized gain on investments
Level 3 |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Net change in unrealized appreciation (depreciation) on investments | $ 984 | $ (12,219)
Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 957,649 | 860,019
Net realized gains (losses) on investments | 12,155 | 24,071
Net change in unrealized appreciation (depreciation) on investments | (6,241) | (10,353)
Purchase of investments | 394,532 | 336,741
Proceeds from sales and repayments of investments | (276,861) | (258,828)
Interest and dividend income paid-in-kind | 7,840 | 6,634
Proceeds from loan origination fees | (2,569) | (3,600)
Accretion of loan origination fees | 2,814 | 2,504
Accretion of original issue discount | 1,187 | 461
Ending Balance | 1,090,506 | 957,649
Subordinated Debt | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 135,173 | 101,456
Net realized gains (losses) on investments |  | 178
Net change in unrealized appreciation (depreciation) on investments | 1,057 | (1,096)
Purchase of investments | 21,966 | 42,041
Proceeds from sales and repayments of investments | (19,689) | (10,328)
Interest and dividend income paid-in-kind | 4,050 | 3,348
Proceeds from loan origination fees | (194) | (622)
Accretion of loan origination fees | 469 | 189
Accretion of original issue discount | 7 | 7
Ending Balance | 142,839 | 135,173
First Lien Debt | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 578,140 | 456,105
Net realized gains (losses) on investments | (3,482) |
Net change in unrealized appreciation (depreciation) on investments | (11,420) | (2,064)
Purchase of investments | 318,608 | 245,741
Proceeds from sales and repayments of investments | (164,986) | (122,680)
Interest and dividend income paid-in-kind | 1,270 | 1,516
Proceeds from loan origination fees | (2,252) | (2,647)
Accretion of loan origination fees | 2,172 | 2,101
Accretion of original issue discount | 70 | 68
Ending Balance | 718,120 | 578,140
Second Lien Debt | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 119,561 | 182,948
Net realized gains (losses) on investments | (2,154) | (10,168)
Net change in unrealized appreciation (depreciation) on investments | (3,462) | 1,461
Purchase of investments | 33,281 | 25,000
Proceeds from sales and repayments of investments | (67,363) | (81,719)
Interest and dividend income paid-in-kind | 2,520 | 1,770
Proceeds from loan origination fees | (123) | (331)
Accretion of loan origination fees | 173 | 214
Accretion of original issue discount | 1,110 | 386
Ending Balance | 83,543 | 119,561
Equity | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 120,007 | 117,431
Net realized gains (losses) on investments | 17,791 | 34,061
Net change in unrealized appreciation (depreciation) on investments | 4,719 | (11,343)
Purchase of investments | 20,677 | 23,959
Proceeds from sales and repayments of investments | (24,823) | (44,101)
Ending Balance | 138,371 | 120,007
Warrant | Level 3 | Fair Value, Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Beginning Balance | 4,768 | 2,079
Net realized gains (losses) on investments | 0 |
Net change in unrealized appreciation (depreciation) on investments | 2,865 | 2,689
Proceeds from sales and repayments of investments | 0 |
Ending Balance | $ 7,633 | $ 4,768

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