Annual report [Section 13 and 15(d), not S-K Item 405]

FAIR VALUE HIERARCHY FOR INVESTMENTS???PORTFOLIO COMPOSITION - Schedule of Changes in Fair Value of Level??3 Portfolio Investments (Details)

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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Schedule of Changes in Fair Value of Level 3 Portfolio Investments (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance $ 4,932,669 $ 4,286,271
Transfers Out of Level 3 Hierarchy (16,810)  
Transfers Into Level 3 Hierarchy   0
Redemptions/ Repayments (969,637) (995,598)
New Investments 1,448,771 1,506,951
Other 0 0
Ending balance 5,496,705 4,932,669
Investments | Net Changes from Unrealized to Realized    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (62,500) (51,289)
Investments | Net Unrealized Appreciation (Depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 164,212 186,334
Debt    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 3,278,365 2,883,917
Transfers Out of Level 3 Hierarchy 0  
Transfers Into Level 3 Hierarchy   0
Redemptions/ Repayments (907,682) (919,626)
New Investments 1,265,274 1,368,567
Other (54,290) (11,501)
Ending balance 3,607,331 3,278,365
Debt | Net Changes from Unrealized to Realized    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 67,307 15,815
Debt | Net Unrealized Appreciation (Depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (41,643) (58,807)
Equity    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 1,637,181 1,395,744
Transfers Out of Level 3 Hierarchy (16,810)  
Transfers Into Level 3 Hierarchy   0
Redemptions/ Repayments (61,355) (75,972)
New Investments 183,497 133,870
Other 54,290 11,501
Ending balance 1,858,205 1,637,181
Equity | Net Changes from Unrealized to Realized    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (130,407) (66,994)
Equity | Net Unrealized Appreciation (Depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 191,809 239,032
Equity Warrant    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 17,123 6,610
Transfers Out of Level 3 Hierarchy 0  
Transfers Into Level 3 Hierarchy   0
Redemptions/ Repayments (600) 0
New Investments 0 4,514
Other 0 0
Ending balance 31,169 17,123
Equity Warrant | Net Changes from Unrealized to Realized    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 600 (110)
Equity Warrant | Net Unrealized Appreciation (Depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 14,046 $ 6,109