Real Estate Securities - Additional Information (Details)	3 Months Ended
Mar. 31, 2024 USD ($) investment Investment	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) investment
Debt and Equity Securities, FV-NI [Line Items]
Number of AFS securities (in investments) \| investment	69		66
Number of securities in unrealized loss position \| investment	13		21
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer (in investments)	12		19
Gross unrealized losses	$ 4,880,000		$ 6,753,000
CECL credit allowance	1,853,000		2,482,000
Sales
Debt and Equity Securities, FV-NI [Line Items]
Gross realized gains	0	$ 1,000,000
Residential
Debt and Equity Securities, FV-NI [Line Items]
AFS securities, contractual maturities, less than five years	4,000,000
Marketable securities, due from five to ten years	7,000,000
CECL credit allowance	$ 19,717,000		$ 23,436,000

Number Of Available for Sale Securities

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

+ References

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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- Definition

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).

+ References

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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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- Definition

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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Amount of realized gain 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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