Fair Value of Financial Instruments - Schedule of Carrying Values and Fair Values of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Carrying Value | Level 1
Assets
Cash and cash equivalents	$ 255,664	$ 245,165
Restricted cash	193,446	67,762
Liabilities
Convertible notes, net	292,993	365,739
Carrying Value | Level 1 | Senior Notes
Liabilities
Senior Notes	321,905	139,989
Carrying Value | Level 2
Liabilities
Debt obligation facilities and other financing	4,045,578	2,818,292
Carrying Value | Level 3
Assets
Residential investor loans held-for-sale	14,414	0
Liabilities
ABS issued, net	58,431	390,674
Trust preferred securities and subordinated notes, net	138,906	138,860
Guarantee obligations	1,267	2,806
Estimated Fair Value | Level 1
Assets
Cash and cash equivalents	255,664	245,165
Restricted cash	193,446	67,762
Liabilities
Convertible notes, net	299,045	365,455
Estimated Fair Value | Level 1 | Senior Notes
Liabilities
Senior Notes	335,904	146,716
Estimated Fair Value | Level 2
Liabilities
Debt obligation facilities and other financing	4,046,266	2,819,393
Estimated Fair Value | Level 3
Assets
Residential investor loans held-for-sale	14,414	0
Liabilities
ABS issued, net	58,386	392,344
Trust preferred securities and subordinated notes, net	80,910	93,465
Guarantee obligations	$ 2,627	$ 3,204