Real Estate Securities - Available for Sale Securities by Collateral Type (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	$ 110,087		$ 87,373
Fair value of securities acquired	14,056	$ 0
Fair value of securities sold	0	2,678
Principal balance of securities called	0	0
Net unrealized gains on AFS securities	8,656	$ 5,007
Mezzanine
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	9,219		0
Sequoia securities
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	87,647		78,942
Multifamily securities
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	4,470		4,460
Other third-party residential securities
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	8,751		3,971
Total Subordinate
Debt and Equity Securities, FV-NI [Line Items]
Available-for-sale	$ 100,868		$ 87,373

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