Real Estate Securities - Additional Information (Details) $ in Thousands	Mar. 31, 2023 USD ($) investment	Dec. 31, 2022 USD ($) investment
Investment Holdings [Line Items]
Number of AFS securities (in investments) \| investment	78	79
Number of securities in unrealized loss position \| investment	37	38
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer (in investments) \| investment	6	1
Gross unrealized losses	$ 10,742	$ 13,127
CECL credit allowance	2,568	2,540
Residential
Investment Holdings [Line Items]
AFS securities, contractual maturities, less than five years	4,000
Marketable securities, due from five to ten years	1,000
CECL credit allowance	$ 28,208	$ 28,739

Number Of Available for Sale Securities

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

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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 sixth through tenth 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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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 allowance 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).

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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