Annual report pursuant to Section 13 and 15(d)

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

v3.24.1
Fair Value Measurements - Changes in Level 3 Portfolio (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Total Investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance $ 4,895,099 $ 0
Purchases of investments 3,355,908 5,089,030
Proceeds from principal repayments and sales of investments (351,925) (114,556)
Transfers into Level 3 11,719 0
Transfers out of Level 3 (79,353) 0
Ending balance 8,028,268 4,895,099
Unrealized gain (loss) 155,397 (88,852)
Total Investments | Accretion of discount/amortization of premium    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 31,814 9,555
Total Investments | Net realized gain (loss)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (164) (78)
Total Investments | Net change in unrealized appreciation (depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 165,170 (88,852)
First lien debt    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 4,882,393 0
Purchases of investments 3,303,363 5,076,535
Proceeds from principal repayments and sales of investments (350,551) (114,556)
Transfers into Level 3 2,256 0
Transfers out of Level 3 (79,353) 0
Ending balance 7,956,235 4,882,393
Unrealized gain (loss) 156,202 (89,041)
First lien debt | Accretion of discount/amortization of premium    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 31,688 9,533
First lien debt | Net realized gain (loss)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 466 (78)
First lien debt | Net change in unrealized appreciation (depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 165,973 (89,041)
Second lien debt    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 8,794 0
Purchases of investments 1,879 8,776
Proceeds from principal repayments and sales of investments 0 0
Transfers into Level 3 9,463 0
Transfers out of Level 3 0 0
Ending balance 19,441 8,794
Unrealized gain (loss) (828) 8
Second lien debt | Accretion of discount/amortization of premium    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 133 10
Second lien debt | Net realized gain (loss)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Second lien debt | Net change in unrealized appreciation (depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (828) 8
Unsecured debt    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 1,606 0
Purchases of investments 14,418 1,651
Proceeds from principal repayments and sales of investments 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Ending balance 15,936 1,606
Unrealized gain (loss) (83) (57)
Unsecured debt | Accretion of discount/amortization of premium    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (7) 12
Unsecured debt | Net realized gain (loss)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Unsecured debt | Net change in unrealized appreciation (depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (81) (57)
Equity investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 2,306 0
Purchases of investments 36,248 2,068
Proceeds from principal repayments and sales of investments (1,374) 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Ending balance 36,656 2,306
Unrealized gain (loss) 106 238
Equity investments | Accretion of discount/amortization of premium    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Equity investments | Net realized gain (loss)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (630) 0
Equity investments | Net change in unrealized appreciation (depreciation)    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 106 $ 238