Real Estate Securities - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) entity investment	Dec. 31, 2021 USD ($) investment
Investment Holdings [Line Items]
Number of AFS securities (in investments) \| investment	82	85
Number of securities in unrealized loss position \| investment	6	4
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer (in investments) \| investment		1
Gross unrealized losses	$ 2,045	$ 297
Additions to allowance for credit losses on securities for which credit losses were not previously recorded	$ 705
Variable Interest Entity, Not Primary Beneficiary
Investment Holdings [Line Items]
Number of entities called \| entity	3
Unpaid principal balance of loans purchased	$ 102,000
Gain related to called security	300
Residential
Investment Holdings [Line Items]
AFS securities, contractual maturities, less than five years	12,000
Marketable securities, due from five to ten years	$ 4,000

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Number of Securities, Continuous Unrealized Loss Position More Than Twelve Months

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Number of Securitization Entities Called

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Unpaid Principal Balance Of Securitization Purchased

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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