Real Estate Securities - Schedule of Trading Securities by Collateral Type (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Investment Holdings [Line Items]
Real estate securities, at fair value	$ 40,424	$ 108,329
Unpaid principal balance	16,567	215,592
Principal balance of securities acquired	7,883	5,006
Principal balance of securities sold	88,073	31,729
Net market valuation gains (losses) recorded	12,694	(34,222)
Senior Securities
Investment Holdings [Line Items]
Real estate securities, at fair value	36,109	28,867
Unpaid principal balance	0	0
Subordinate
Investment Holdings [Line Items]
Real estate securities, at fair value	4,315	79,462
Unpaid principal balance	16,567	215,592
Interest-only securities \| Senior Securities
Investment Holdings [Line Items]
Real estate securities, at fair value	36,109	28,867
Interest-only securities \| Senior Securities \| Sequoia
Investment Holdings [Line Items]
Real estate securities, at fair value	28,000	26,000
RPL securities \| Subordinate
Investment Holdings [Line Items]
Real estate securities, at fair value	0	29,002
Multifamily securities \| Subordinate
Investment Holdings [Line Items]
Real estate securities, at fair value	2,641	5,027
Other third-party residential securities \| Subordinate
Investment Holdings [Line Items]
Real estate securities, at fair value	$ 1,674	$ 45,433

Amount of increase (decrease) of investment in debt and equity securities, measured at fair value with changes in fair value recognized in net income.

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Amount of principal of investment owned.

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The cash outflow to acquire securities classified as trading securities and held for investment purposes. Excludes payments for trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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