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Fair Value - Level III Rollforward (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Total |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | $ 2,938,849 | $ 3,136,291
Purchases, including capitalized PIK and revolver fundings | 848,075 | 349,003
Proceeds from sales and paydowns of investments | (785,213) | (582,011)
Transfers into Level III | 28,440 | 63,087
Transfers out of Level III | (24,996) | (11,490)
Ending balance | 2,987,078 | 2,938,849
Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: | (23,320) | (34,144)
Total | Net realized (losses) gains on investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | (46,487) | (33,048)
Total | Net change in unrealized appreciation (depreciation) of investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | 28,410 | 17,017
First lien |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 1,637,889 | 1,753,967
Purchases, including capitalized PIK and revolver fundings | 750,811 | 302,949
Proceeds from sales and paydowns of investments | (516,980) | (407,081)
Transfers into Level III | 28,440 | 0
Transfers out of Level III | 0 | (11,490)
Ending balance | 1,902,610 | 1,637,889
Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: | 1,670 | 12,890
First lien | Net realized (losses) gains on investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | (13,477) | (41,767)
First lien | Net change in unrealized appreciation (depreciation) of investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | 15,927 | 41,311
Second lien |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 406,180 | 480,068
Purchases, including capitalized PIK and revolver fundings | 5,555 | 4,484
Proceeds from sales and paydowns of investments | (242,523) | (140,837)
Transfers into Level III | 0 | 63,087
Transfers out of Level III | (24,996) | 0
Ending balance | 150,334 | 406,180
Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: | 1,135 | 1,625
Second lien | Net realized (losses) gains on investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | (35,085) | (24,627)
Second lien | Net change in unrealized appreciation (depreciation) of investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | 41,203 | 24,005
Subordinated |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 82,871 | 72,842
Purchases, including capitalized PIK and revolver fundings | 21,059 | 10,141
Proceeds from sales and paydowns of investments | (292) | 0
Transfers into Level III | 0 | 0
Transfers out of Level III | 0 | 0
Ending balance | 102,034 | 82,871
Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: | (1,607) | (4)
Subordinated | Net realized (losses) gains on investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | 3 | 0
Subordinated | Net change in unrealized appreciation (depreciation) of investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | (1,607) | (112)
Equity and other |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 811,909 | 829,414
Purchases, including capitalized PIK and revolver fundings | 70,650 | 31,429
Proceeds from sales and paydowns of investments | (25,418) | (34,093)
Transfers into Level III | 0 | 0
Transfers out of Level III | 0 | 0
Ending balance | 832,100 | 811,909
Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: | (24,518) | (48,655)
Equity and other | Net realized (losses) gains on investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | 2,072 | 33,346
Equity and other | Net change in unrealized appreciation (depreciation) of investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total gains or losses included in earnings | $ (27,113) | $ (48,187)

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