FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Schedule of Investments (Details) $ in Thousands |
12 Months Ended | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2025
USD ($)
company
|
Dec. 31, 2024
USD ($)
company
|
|||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Fair value | $ 5,518,117 | [1],[2],[3] | $ 4,932,669 | [4],[5],[6] | ||||||||||||||||
| Cost | $ 4,724,528 | [1],[3],[7] | $ 4,237,312 | [4],[6],[8] | ||||||||||||||||
| Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 100.00% | 100.00% | ||||||||||||||||||
| Investment Owned, At Cost | Investment Type Concentration Risk | Non-accrual Status | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 3.30% | 3.50% | ||||||||||||||||||
| Equity | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 18.60% | 16.40% | ||||||||||||||||||
| First lien debt | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 80.90% | 82.90% | ||||||||||||||||||
| LMM portfolio investments | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Number of portfolio companies | company | 92 | 84 | ||||||||||||||||||
| Fair value | $ 3,057,000 | $ 2,502,900 | ||||||||||||||||||
| Cost | $ 2,419,300 | $ 1,937,800 | ||||||||||||||||||
| Weighted-average annual effective yield (as a percent) | 12.50% | 12.80% | ||||||||||||||||||
| Average EBITDA | $ 11,100 | $ 10,200 | ||||||||||||||||||
| Diluted equity ownership (as a percent) | 37.00% | 38.00% | ||||||||||||||||||
| Investment company, number of companies within portfolio excluded from EBITDA calculation | company | 5 | 5 | ||||||||||||||||||
| LMM portfolio investments | Non-accrual Status | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Weighted-average annual effective yield (as a percent) | 12.00% | 12.30% | ||||||||||||||||||
| LMM portfolio investments | Debt | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 71.20% | 70.80% | ||||||||||||||||||
| LMM portfolio investments | Equity | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 28.80% | 29.20% | ||||||||||||||||||
| LMM portfolio investments | First lien debt | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 99.40% | 99.20% | ||||||||||||||||||
| Private Loan portfolio investments | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Number of portfolio companies | company | 86 | 91 | ||||||||||||||||||
| Fair value | $ 1,988,400 | $ 1,904,300 | ||||||||||||||||||
| Cost | $ 2,014,100 | $ 1,952,500 | ||||||||||||||||||
| Weighted-average annual effective yield (as a percent) | 10.50% | 11.80% | ||||||||||||||||||
| Average EBITDA | $ 33,900 | $ 30,500 | ||||||||||||||||||
| Investment company, number of companies within portfolio excluded from EBITDA calculation | company | 6 | 5 | ||||||||||||||||||
| Private Loan portfolio investments | Non-accrual Status | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Weighted-average annual effective yield (as a percent) | 10.10% | 11.50% | ||||||||||||||||||
| Private Loan portfolio investments | Debt | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 93.50% | 95.40% | ||||||||||||||||||
| Private Loan portfolio investments | Equity | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 6.50% | 4.60% | ||||||||||||||||||
| Private Loan portfolio investments | First lien debt | Investment Owned, At Cost | Investment Type Concentration Risk | ||||||||||||||||||||
| Summary of Investment Holdings [Line Items] | ||||||||||||||||||||
| Concentration risk (as a percent) | 99.90% | 99.90% | ||||||||||||||||||
| ||||||||||||||||||||