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Fair Value - Fair Value Levels (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | $ 3,213,780 | $ 3,011,322
First lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 2,017,636 | 1,683,952
Second lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 276,961 | 424,513
Subordinated |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 106,788 | 90,948
Equity and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 812,395 | 811,909
Level I |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level I | First lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level I | Second lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level I | Subordinated |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level I | Equity and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level II |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 115,588 | 72,473
Level II | First lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 44,556 | 46,063
Level II | Second lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 60,897 | 18,333
Level II | Subordinated |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 10,135 | 8,077
Level II | Equity and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 0 | 0
Level III |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 3,098,192 | 2,938,849
Level III | First lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 1,973,080 | 1,637,889
Level III | Second lien |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 216,064 | 406,180
Level III | Subordinated |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | 96,653 | 82,871
Level III | Equity and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments | $ 812,395 | $ 811,909

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