Fair Value of Investments - Schedule of Carrying and Fair Values of the Company’s Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Fair value of debt obligations	$ 6,689,063	$ 6,909,235
Debt issuance costs, net	85,969	95,647
Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	7,027,176	7,281,744
Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	6,689,063	6,909,235
Level 1
Debt Instrument [Line Items]
Fair value of debt obligations	0	0
Level 2
Debt Instrument [Line Items]
Fair value of debt obligations	3,724,750	3,679,375
Level 3
Debt Instrument [Line Items]
Fair value of debt obligations	2,964,313	3,229,860
Line of Credit | SPV Asset Facility II
Debt Instrument [Line Items]
Debt issuance costs, net	4,500	4,600
Line of Credit | SPV Asset Facility II | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	135,524	245,368
Line of Credit | SPV Asset Facility II | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	135,524	245,368
Line of Credit | SPV Asset Facility III
Debt Instrument [Line Items]
Debt issuance costs, net		600
Line of Credit | SPV Asset Facility III | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	0	249,372
Line of Credit | SPV Asset Facility III | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	0	249,372
Line of Credit | CLO I
Debt Instrument [Line Items]
Debt issuance costs, net		2,700
Secured Debt | CLO I
Debt Instrument [Line Items]
Debt issuance costs, net	2,500	2,700
Secured Debt | CLO I | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	387,487	387,321
Secured Debt | CLO I | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	387,487	387,321
Secured Debt | CLO II
Debt Instrument [Line Items]
Debt issuance costs, net	2,700	2,800
Secured Debt | CLO II | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	257,347	257,206
Secured Debt | CLO II | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	257,347	257,206
Secured Debt | CLO III
Debt Instrument [Line Items]
Debt issuance costs, net	1,800	1,900
Secured Debt | CLO III | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,207	258,145
Secured Debt | CLO III | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,207	258,145
Secured Debt | CLO IV
Debt Instrument [Line Items]
Debt issuance costs, net	4,500	4,700
Secured Debt | CLO IV | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	287,987	287,777
Secured Debt | CLO IV | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	287,987	287,777
Secured Debt | CLO V
Debt Instrument [Line Items]
Debt issuance costs, net	2,700	2,800
Secured Debt | CLO V | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	506,889	506,792
Secured Debt | CLO V | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	506,889	506,792
Secured Debt | CLO VI
Debt Instrument [Line Items]
Debt issuance costs, net	1,700	1,700
Secured Debt | CLO VI | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,325	258,271
Secured Debt | CLO VI | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,325	258,271
Secured Debt | CLO VII
Debt Instrument [Line Items]
Debt issuance costs, net	1,900	2,000
Secured Debt | CLO VII | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	237,238	237,155
Secured Debt | CLO VII | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	237,238	237,155
Secured Debt | CLO X
Debt Instrument [Line Items]
Debt issuance costs, net	1,900
Secured Debt | CLO X | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,072	0
Secured Debt | CLO X | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	258,072	0
Unsecured debt | 2024 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	1,800	2,900
Unsecured debt | 2024 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	388,496	384,851
Unsecured debt | 2024 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	395,000	395,000
Unsecured debt | 2025 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	3,000	3,800
Unsecured debt | 2025 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	422,050	421,242
Unsecured debt | 2025 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	399,500	399,500
Unsecured debt | July 2025 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	3,800	4,700
Unsecured debt | July 2025 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	496,222	495,347
Unsecured debt | July 2025 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	462,500	462,500
Unsecured debt | 2026 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	5,800	6,800
Unsecured debt | 2026 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	494,232	493,162
Unsecured debt | 2026 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	462,500	461,250
Unsecured debt | July 2026 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	14,700	17,000
Unsecured debt | July 2026 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	985,271	982,993
Unsecured debt | July 2026 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	887,500	875,000
Unsecured debt | 2027 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	7,000	7,900
Unsecured debt | 2027 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	439,434	438,332
Unsecured debt | 2027 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	425,000	412,500
Unsecured debt | 2028 Notes
Debt Instrument [Line Items]
Debt issuance costs, net	12,800	14,000
Unsecured debt | 2028 Notes | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	837,158	835,957
Unsecured debt | 2028 Notes | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	692,750	673,625
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Debt issuance costs, net	12,900	14,700
Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Debt issuance costs, net	12,900	14,700
Revolving Credit Facility | Line of Credit | Revolving Credit Facility | Net Carrying Value
Debt Instrument [Line Items]
Fair value of debt obligations	377,237	542,453
Revolving Credit Facility | Line of Credit | Revolving Credit Facility | Fair Value
Debt Instrument [Line Items]
Fair value of debt obligations	$ 377,237	$ 542,453