Real Estate Securities - Additional Information (Details) $ in Thousands	Dec. 31, 2020 USD ($) investment	Dec. 31, 2019 USD ($) investment
Investment Holdings [Line Items]
Number of AFS securities \| investment	96	107
Number of securities in unrealized loss position \| investment	5	1
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer \| investment	0	1
Gross unrealized losses	$ 1,047	$ 29
AFS securities, allowance for credit loss	388	$ 0
Residential
Investment Holdings [Line Items]
Marketable securities, less than five years	41,000
Marketable securities, due from five to ten years	$ 3,000

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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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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