Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Changes in Level 3 Portfolio (Details)

v3.23.3
Fair Value Measurements - Changes in Level 3 Portfolio (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2023
Sep. 30, 2022
Sep. 30, 2023
Sep. 30, 2022
First lien debt        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance $ 6,104,163 $ 2,154,718 $ 4,882,393 $ 0
Purchases of investments 778,508 1,626,852 2,071,394 3,888,670
Proceeds from principal repayments and sales of investments (96,696) (7,931) (266,254) (100,312)
Transfers into Level 3 2,272 0 2,272 0
Transfers out of Level 3 (136,235) 0 (140,949) 0
Ending balance 6,681,145 3,710,030 6,681,145 3,710,030
Net change in unrealized appreciation (depreciation) related to financial instruments still held 18,897 (66,587) 98,971 (83,814)
First lien debt | Accretion (Amortization) of Discounts and Premiums, Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 8,596 3,023 24,198 5,520
First lien debt | Debt and Equity Securities, Realized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 21 (45) 981 (34)
First lien debt | Debt and Equity Securities, Unrealized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 20,516 (66,587) 107,110 (83,814)
Second lien debt        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 20,039 8,780 8,794 0
Purchases of investments 0 0 1,879 8,776
Proceeds from principal repayments and sales of investments 0 0 0 0
Transfers into Level 3 0 0 9,463 0
Transfers out of Level 3 0 0 0 0
Ending balance 20,382 8,787 20,382 8,787
Net change in unrealized appreciation (depreciation) related to financial instruments still held 306 3 151 4
Second lien debt | Accretion (Amortization) of Discounts and Premiums, Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 37 4 95 7
Second lien debt | Debt and Equity Securities, Realized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 0 0 0 0
Second lien debt | Debt and Equity Securities, Unrealized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 306 3 151 4
Unsecured debt        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 1,975 0 1,606 0
Purchases of investments 329 725 772 725
Proceeds from principal repayments and sales of investments 0 0 0 0
Transfers into Level 3 0 0 0 0
Transfers out of Level 3 0 0 0 0
Ending balance 2,342 725 2,342 725
Net change in unrealized appreciation (depreciation) related to financial instruments still held 37 (3) (30) (3)
Unsecured debt | Accretion (Amortization) of Discounts and Premiums, Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 1 3 (9) 3
Unsecured debt | Debt and Equity Securities, Realized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 0 0 0 0
Unsecured debt | Debt and Equity Securities, Unrealized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 37 (3) (27) (3)
Equity investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 4,729 67 2,306 0
Purchases of investments 8,533 2,001 11,446 2,068
Proceeds from principal repayments and sales of investments (197) 0 (374) 0
Transfers into Level 3 0 0 0 0
Transfers out of Level 3 0 0 0 0
Ending balance 12,709 2,069 12,709 2,069
Net change in unrealized appreciation (depreciation) related to financial instruments still held (385) 1 (296) 1
Equity investments | Accretion (Amortization) of Discounts and Premiums, Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 0 0 0 0
Equity investments | Debt and Equity Securities, Realized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 29 0 (373) 0
Equity investments | Debt and Equity Securities, Unrealized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings (385) 1 (296) 1
Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 6,130,906 2,163,565 4,895,099 0
Purchases of investments 787,370 1,629,578 2,085,491 3,900,239
Proceeds from principal repayments and sales of investments (96,893) (7,931) (266,628) (100,312)
Transfers into Level 3 2,272 0 11,735 0
Transfers out of Level 3 (136,235) 0 (140,949) 0
Ending balance 6,716,578 3,721,611 6,716,578 3,721,611
Net change in unrealized appreciation (depreciation) related to financial instruments still held 18,855 (66,586) 98,796 (83,812)
Investments | Accretion (Amortization) of Discounts and Premiums, Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 8,634 3,030 24,284 5,530
Investments | Debt and Equity Securities, Realized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings 50 (45) 608 (34)
Investments | Debt and Equity Securities, Unrealized Gain (Loss)        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain (loss) included in earnings $ 20,474 $ (66,586) $ 106,938 $ (83,812)