Secured Borrowings - Collateral Pledged (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Secured borrowings
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	$ 3,320,583
Secured borrowings | Asset pledged as collateral without right
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	3,320,583	$ 3,931,876
Borrowings under credit facilities and other financing arrangements
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	212,512
Borrowings under credit facilities and other financing arrangements | Asset pledged as collateral without right | Loans and finance receivables
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	212,512	588,866
Borrowings under repurchase agreements
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	3,108,071
Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	3,108,071	3,343,010
Real estate acquired in settlement of loans | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	160,455	1,491
Loans, held for sale, at fair value | Borrowings under credit facilities and other financing arrangements | Asset pledged as collateral without right | Loans and finance receivables
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	43,365	13,791
Loans, held for sale, at fair value | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses		60,551
Loans, net | Borrowings under credit facilities and other financing arrangements | Asset pledged as collateral without right | Loans and finance receivables
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	169,147	575,075
Loans, net | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	2,560,725	2,496,880
Loans, held at fair value | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	9,349	3,974
Mortgage backed securities | Borrowings under repurchase agreements
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	377,542
Mortgage backed securities | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	20,770	27,015
Retained interest in assets of consolidated VIEs | Borrowings under repurchase agreements | Asset pledged as collateral without right | Securities sold under agreements to repurchase
Collateral pledged
Total Loans, in consolidated VIEs, before allowance for loan losses	$ 356,772	$ 753,099