Fair Value Measurement - Schedule of Carrying Values and Fair Values of Debt Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	$ 12,452,159	$ 10,671,928
Carrying Value | Recourse debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	996,034	932,369
Carrying Value | Senior debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	4,135,861	4,114,134
Carrying Value | Subordinated debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	2,638,532	2,219,573
Carrying Value | Securitization debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	4,681,732	3,405,852
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	12,413,344	10,251,257
Fair Value | Recourse debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	1,152,113	844,727
Fair Value | Senior debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	4,125,315	4,082,994
Fair Value | Subordinated debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	2,573,620	2,131,994
Fair Value | Securitization debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	$ 4,562,296	$ 3,191,542