Fair Value of Financial Instruments - Schedule of Carrying Values and Fair Values of Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Carrying Value \| Level 1
Assets
Cash and cash equivalents	$ 191,846	$ 255,664
Restricted cash	99,465	193,446
Liabilities
Convertible notes, net	294,369	292,993
Carrying Value \| Level 2
Liabilities
Debt obligation facilities and other financing	4,079,669	4,045,578
Carrying Value \| Level 3
Assets
Residential investor loans held-for-sale	13,863	14,414
Liabilities
ABS issued, net	0	58,431
Trust preferred securities and subordinated notes, net	138,929	138,906
Guarantee obligations	3,689	1,267
Carrying Value \| Senior Notes \| Level 1
Liabilities
Senior Notes	443,607	321,905
Estimated Fair Value \| Level 1
Assets
Cash and cash equivalents	191,846	255,664
Restricted cash	99,465	193,446
Liabilities
Convertible notes, net	300,439	299,045
Estimated Fair Value \| Level 2
Liabilities
Debt obligation facilities and other financing	4,080,151	4,046,266
Estimated Fair Value \| Level 3
Assets
Residential investor loans held-for-sale	13,863	14,414
Liabilities
ABS issued, net	0	58,386
Trust preferred securities and subordinated notes, net	78,120	80,910
Guarantee obligations	3,689	2,627
Estimated Fair Value \| Senior Notes \| Level 1
Liabilities
Senior Notes	$ 451,517	$ 335,904

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Trust Preferred Securities And Subordinated Notes, Net, Fair Value Disclosure

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Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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