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INVESTMENTS - Schedule of Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 2,244,908 | $ 2,237,531
New investments | 402,412 | 212,752
Investment restructuring |  | (22,249)
Transfers into Level 3 | 5,989 |
Transfers out of Level 3 | (13,918) |
Transfers into (out of) Level 3, net |  | (1,992)
Proceeds from sales of investments / return of capital | (71,943) | (24,527)
Loan origination fees received | (8,243) | (3,769)
Principal repayments received | (168,843) | (223,865)
Fair value end of period | 2,441,403 | 2,167,560
Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 13,444 | $ 9,559
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 159 | $ 276
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 5,213 | $ 5,456
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (24,721) | $ (16,332)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 56,946 | $ (5,280)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Senior debt and 1st lien notes |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 1,625,501 | $ 1,593,797
New investments | 331,359 | 176,984
Investment restructuring |  | (22,249)
Transfers into Level 3 | 0 |
Transfers out of Level 3 | 0 |
Transfers into (out of) Level 3, net |  | (1,862)
Proceeds from sales of investments / return of capital | (61,189) | (18,512)
Loan origination fees received | (6,628) | (3,473)
Principal repayments received | (121,005) | (191,286)
Fair value end of period | 1,795,252 | 1,519,947
Senior debt and 1st lien notes | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 4,148 | $ 2,002
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Senior debt and 1st lien notes | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 159 | $ 221
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Senior debt and 1st lien notes | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 4,626 | $ 4,969
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Senior debt and 1st lien notes | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (18,792) | $ (7,040)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Senior debt and 1st lien notes | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 37,073 | $ (13,604)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Subordinated debt and 2nd lien notes |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 153,703 | $ 223,798
New investments | 46,395 | 26,325
Investment restructuring |  | 0
Transfers into Level 3 | 5,989 |
Transfers out of Level 3 | (6,523) |
Transfers into (out of) Level 3, net |  | 0
Proceeds from sales of investments / return of capital | (3) | (4,975)
Loan origination fees received | (1,615) | (296)
Principal repayments received | (16,935) | (32,222)
Fair value end of period | 184,616 | 213,023
Subordinated debt and 2nd lien notes | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 2,267 | $ 1,708
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Subordinated debt and 2nd lien notes | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 55
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Subordinated debt and 2nd lien notes | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 444 | $ 487
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Subordinated debt and 2nd lien notes | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (9,417) | $ (5,107)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Subordinated debt and 2nd lien notes | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 10,311 | $ 3,250
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Structured products |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 48,664 | $ 42,972
New investments | 7,500 | 48
Investment restructuring |  | 0
Transfers into Level 3 | 0 |
Transfers out of Level 3 | (3,310) |
Transfers into (out of) Level 3, net |  | 0
Proceeds from sales of investments / return of capital | (1,933) | 0
Loan origination fees received | 0 | 0
Principal repayments received | (30,903) | (357)
Fair value end of period | 19,254 | 45,500
Structured products | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Structured products | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Structured products | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 143 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Structured products | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (1,595) | $ (6)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Structured products | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 688 | $ 2,843
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Equity shares |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 408,475 | $ 374,572
New investments | 17,158 | 5,524
Investment restructuring |  | 0
Transfers into Level 3 | 0 |
Transfers out of Level 3 | (4,085) |
Transfers into (out of) Level 3, net |  | (130)
Proceeds from sales of investments / return of capital | (4,065) | (1,040)
Loan origination fees received | 0 | 0
Principal repayments received | 0 | 0
Fair value end of period | 439,652 | 382,595
Equity shares | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 7,029 | $ 5,849
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Equity shares | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Equity shares | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Equity shares | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 2,616 | $ (4,179)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Equity shares | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 12,524 | $ 1,999
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Equity warrants |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 2,732 | $ 2,392
New investments | 0 | 0
Investment restructuring |  | 0
Transfers into Level 3 | 0 |
Transfers out of Level 3 | 0 |
Transfers into (out of) Level 3, net |  | 0
Proceeds from sales of investments / return of capital | 0 | 0
Loan origination fees received | 0 | 0
Principal repayments received | 0 | 0
Fair value end of period | 1,087 | 2,624
Equity warrants | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income | Total payment-in-kind interest income
Equity warrants | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Equity warrants | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees | Interest and other financing fees
Equity warrants | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments | Net realized gains (losses) on investments
Equity warrants | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (1,645) | $ 232
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments | Net unrealized appreciation (depreciation) on investments
Royalty rights |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value beginning of period | $ 5,833 | $ 0
New investments | 0 | 3,871
Investment restructuring |  | 0
Transfers into Level 3 | 0 |
Transfers out of Level 3 | 0 |
Transfers into (out of) Level 3, net |  | 0
Proceeds from sales of investments / return of capital | (4,753) | 0
Loan origination fees received | 0 | 0
Principal repayments received | 0 | 0
Fair value end of period | 1,542 | 3,871
Royalty rights | Payment-in-kind interest / dividends |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Total payment-in-kind interest income |
Royalty rights | Accretion of loan premium / discount |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees |
Royalty rights | Accretion of deferred loan origination revenue |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 0 | 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and other financing fees |
Royalty rights | Realized gain (loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ 2,467 | 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net realized gains (losses) on investments |
Royalty rights | Unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value recurring basis gain (losses) | $ (2,005) | $ 0
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) on investments |

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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Loan Origination Fees Received + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Principal Repayment Received + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Restructuring + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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