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Fair Value Measurement - Summary of Changes in Fair Value of Level 3 Assets By Investment Type (Details) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2026 | Jun. 30, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Amortization of Premium/Discount |  | $ 7,820 | $ 11,062
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | $ (81,751) | $ (9,057)
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Gain (Loss) on Investments | Gain (Loss) on Investments
1st Lien/Senior Secured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | $ (57,871) | $ (6,586)
1st Lien/Last-Out Unitranche |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | (5,034) | 2,182
2nd Lien/Senior Secured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | (12,893) | 835
Unsecured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | (536) | 432
Preferred Stock |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | (6,303) | 1,286
Common Stock |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | 726 | (7,183)
Warrants |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Net Change in Unrealized Appreciation (Depreciation) for assets still held |  | 160 | (23)
Level 3 |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 3,207,527 | 3,431,997
Purchases | [1] | 282,547 | 401,517
Net Realized Gain (Loss) |  | $ 21,330 | $ (125,691)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Debt and Equity Securities, Realized Gain (Loss) | Debt and Equity Securities, Realized Gain (Loss)
Net Change in Unrealized Appreciation (Depreciation) |  | $ (82,273) | $ 106,668
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] |  | Debt and Equity Securities, Unrealized Gain (Loss) | Debt and Equity Securities, Unrealized Gain (Loss)
Sales and Settlements | [2] | $ (295,627) | $ (598,618)
Net Amortization of Premium/Discount |  | 7,814 | 11,050
Transfers In | [3] | 34,011 | 18,015
Transfers Out | [3] | 0 | 0
Ending Balance |  | 3,175,329 | 3,244,938
Level 3 | 1st Lien/Senior Secured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 2,974,646 | 3,136,683
Purchases | [1] | 239,414 | 365,336
Net Realized Gain (Loss) |  | (174) | (94,768)
Net Change in Unrealized Appreciation (Depreciation) |  | (53,176) | 78,152
Sales and Settlements | [2] | (258,087) | (588,881)
Net Amortization of Premium/Discount |  | 6,827 | 10,421
Transfers In | [3] | 34,011 | 18,015
Transfers Out | [3] | 0 | 0
Ending Balance |  | 2,943,461 | 2,924,958
Level 3 | 1st Lien/Last-Out Unitranche |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 135,156 | 165,905
Purchases | [1] | 6,550 | 19,162
Net Realized Gain (Loss) |  | 0 | 0
Net Change in Unrealized Appreciation (Depreciation) |  | (5,051) | 2,181
Sales and Settlements | [2] | (4,646) | (371)
Net Amortization of Premium/Discount |  | 146 | 459
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 | 0
Ending Balance |  | 132,155 | 187,336
Level 3 | 2nd Lien/Senior Secured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 47,914 | 46,786
Purchases | [1] | 34,926 | 1,819
Net Realized Gain (Loss) |  | 21,504 | (9,031)
Net Change in Unrealized Appreciation (Depreciation) |  | (18,093) | 9,865
Sales and Settlements | [2] | (31,548) | 0
Net Amortization of Premium/Discount |  | 415 | (80)
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 | 0
Ending Balance |  | 55,118 | 49,359
Level 3 | Unsecured Debt |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 8,476 | 16,790
Purchases | [1] | 1,549 | 109
Net Realized Gain (Loss) |  | 0 | (1,055)
Net Change in Unrealized Appreciation (Depreciation) |  | (536) | 1,553
Sales and Settlements | [2] | (1,346) | (9,366)
Net Amortization of Premium/Discount |  | 426 | 250
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 | 0
Ending Balance |  | 8,569 | 8,281
Level 3 | Preferred Stock |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 26,426 | 31,246
Purchases | [1] | 108 | 8,698
Net Realized Gain (Loss) |  | 0 | (778)
Net Change in Unrealized Appreciation (Depreciation) |  | (6,303) | 2,064
Sales and Settlements | [2] | 0 | 0
Net Amortization of Premium/Discount |  | 0 | 0
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 | 0
Ending Balance |  | 20,231 | 41,230
Level 3 | Common Stock |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 14,662 | 34,166
Purchases | [1] | 0 | 6,393
Net Realized Gain (Loss) |  | 0 | (20,059)
Net Change in Unrealized Appreciation (Depreciation) |  | 726 | 12,876
Sales and Settlements | [2] | 0 | 0
Net Amortization of Premium/Discount |  | 0 | 0
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 | 0
Ending Balance |  | 15,388 | 33,376
Level 3 | Warrants |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Beginning Balance |  | 247 | 421
Purchases | [1] | 0 | 0
Net Realized Gain (Loss) |  | 0 | 0
Net Change in Unrealized Appreciation (Depreciation) |  | 160 | (23)
Sales and Settlements | [2] | 0 | 0
Net Amortization of Premium/Discount |  | 0 | 0
Transfers In | [3] | 0 | 0
Transfers Out | [3] | 0 |
Ending Balance |  | $ 407 | $ 398
[1] | Purchases may include PIK, securities received in corporate actions and restructurings.
[2] | Sales and Settlements may include securities delivered in corporate actions and restructuring of investments.
[3] | Transfers in (out) of Level 3 are due to a decrease (increase) in the quantity and reliability of broker quotes obtained by the Investment Adviser.

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