Securitizations and Variable Interest Entities - Summary of Activity Related to Unconsolidated VIEs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair value of consideration received:
Cash	$ 0	$ 0	$ 106,192
Unconsolidated
Fair value of consideration received:
Cash	172,397	5,320	0
Asset-backed securities retained	1,299,313	2,180	0
Other assets (liabilities)	16,740	(3,794)	0
Total consideration	1,488,450	3,706	0
Deconsolidation of debt	0	36,072	0
Fair value of loans sold	(1,474,077)	(39,519)	0
Gain on sales of loans	14,373	259	0
Cash proceeds from continuing involvement:
Servicing and other administrative fees	5,475	8,618	23,586
Interest received on asset-backed securities retained	$ 22,786	$ 7,285	$ 9,136