Real Estate Securities - Narrative (Details)	12 Months Ended
Dec. 31, 2024 USD ($) Investment	Dec. 31, 2023 USD ($) Investment	Dec. 31, 2022 USD ($)
Investment Holdings [Line Items]
Net unrealized gain (loss) on available-for-sale securities	$ 12,345,000	$ 6,230,000	$ (64,704,000)
Accretion income on AFS securities	$ 2,000,000	$ 1,000,000	11,000,000
Number of AFS securities \| Investment	90	66
Number of securities in unrealized loss position \| Investment	20	21
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer \| Investment	11	19
CECL credit allowance	$ 921,000	$ 2,482,000	$ 2,540,000
Sales
Investment Holdings [Line Items]
Gross realized gains	0	$ 2,000,000
Residential
Investment Holdings [Line Items]
Marketable securities, less than five years	49,000,000
Marketable securities, due from five to ten years	$ 4,000,000

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

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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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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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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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Amount of interest income, amortization of premium and accretion of discount on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale); classified as operating.

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