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Amount of principal of investment owned.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Real Estate Securities - Trading Securities by Collateral Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	$ 119,624		$ 119,624		$ 40,424
Unpaid principal balance	16,098		16,098		16,567
Fair value of securities acquired	16,092	$ 6,183	63,618	$ 7,883
Fair value of securities sold	0	51,578	0	55,087
Net market valuation gains (losses) recorded	1,600	$ 6,495	16,075	$ 8,456
Senior
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	115,287		115,287		36,109
Unpaid principal balance	0		0		0
Subordinate
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	4,337		4,337		4,315
Unpaid principal balance	16,098		16,098		16,567
Interest-only securities \| Senior
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	115,287		115,287		36,109
Interest-only securities \| Senior \| Sequoia
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	32,000		32,000		28,000
Multifamily securities \| Subordinate
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	2,823		2,823		2,641
Other third-party securities \| Subordinate
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, and equity securities, Fair Value	$ 1,514		$ 1,514		$ 1,674