Borrowings - Schedule of Company's Outstanding Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Nov. 21, 2024	Sep. 15, 2023	Apr. 07, 2022
Borrowings
Aggregate Principal Amount Committed	$ 3,780,439	$ 2,656,207
Principal Amount Outstanding	2,775,533	2,151,713
Carrying Value	2,748,236	2,128,362
Unamortized Debt Issuance Costs	27,297	23,351
Revolving Credit Facility
Borrowings
Aggregate Principal Amount Committed	785,000	652,500
Principal Amount Outstanding	365,194	481,106
Carrying Value	359,510	474,756
Unamortized Debt Issuance Costs	5,684	6,350
SPV Credit Facility
Borrowings
Aggregate Principal Amount Committed	450,000	450,000
Principal Amount Outstanding	89,900	243,300
Carrying Value	87,210	239,889
Unamortized Debt Issuance Costs	2,690	3,411
SPV II Credit Facility
Borrowings
Aggregate Principal Amount Committed	690,000	195,998
Principal Amount Outstanding	527,400	195,998
Carrying Value	522,402	194,574
Unamortized Debt Issuance Costs	4,998	1,424
SPV III Credit Facility
Borrowings
Aggregate Principal Amount Committed	200,000	100,000
Principal Amount Outstanding	187,000	75,000
Carrying Value	185,409	73,722
Unamortized Debt Issuance Costs	1,591	1,278
SPV IV Credit Facility
Borrowings
Aggregate Principal Amount Committed	350,000	350,000
Principal Amount Outstanding	319,000	248,600
Carrying Value	316,309	245,185
Unamortized Debt Issuance Costs	2,691	3,415
SPV V Credit Facility
Borrowings
Aggregate Principal Amount Committed	250,000
Principal Amount Outstanding	231,600
Carrying Value	229,175	0
Unamortized Debt Issuance Costs	2,425
2022 ABS
Borrowings
Aggregate Principal Amount Committed	239,339	294,609			$ 425,000
Principal Amount Outstanding	239,339	294,609
Carrying Value	239,339	293,393
Unamortized Debt Issuance Costs	0	1,216
2022 Class C Notes
Borrowings
Carrying Value	28,255	34,780
2022 Subordinated Notes
Borrowings
Carrying Value	82,875	82,875
2023 ABS
Borrowings
Aggregate Principal Amount Committed	209,100	209,100		$ 251,169
Principal Amount Outstanding	209,100	209,100
Carrying Value	207,041	206,369
Unamortized Debt Issuance Costs	2,059	2,731
2028 Notes
Borrowings
Aggregate Principal Amount Committed	200,000	200,000
Principal Amount Outstanding	200,000	200,000
Carrying Value	198,529	198,178
Unamortized Debt Issuance Costs	1,471	1,822
2029 Notes
Borrowings
Aggregate Principal Amount Committed	204,000	204,000
Principal Amount Outstanding	204,000	204,000
Carrying Value	202,573	202,296
Unamortized Debt Issuance Costs	1,427	1,704
July 2028 Notes
Borrowings
Aggregate Principal Amount Committed	42,000
Principal Amount Outstanding	42,000
Carrying Value	41,544	0
Unamortized Debt Issuance Costs	456
July 2030 Notes
Borrowings
Aggregate Principal Amount Committed	161,000
Principal Amount Outstanding	161,000
Carrying Value	159,195	0
Unamortized Debt Issuance Costs	1,805
2023 Subordinated Notes
Borrowings
Aggregate Principal Amount Committed			$ 45,900	$ 65,319
Carrying Value	$ 45,900	$ 45,900