Real Estate Securities - Additional Information (Details) $ in Thousands	Dec. 31, 2022 USD ($) investment	Dec. 31, 2021 USD ($) investment	Dec. 31, 2020 USD ($)
Investment Holdings [Line Items]
Number of AFS securities \| investment	79	85
Number of securities in unrealized loss position \| investment	38	4
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer \| investment	1	1
Gross unrealized losses	$ 13,127	$ 297
CECL credit allowance	2,540	$ 0	$ 388
Residential
Investment Holdings [Line Items]
Marketable securities, less than five years	4,000
Marketable securities, due from five to ten years	$ 1,000

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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