Net Interest Income - Components of Interest Income and Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Interest income	$ 58,501	$ 50,039
Interest expense	28,622	19,699
Total net interest income	29,879	30,340
Convertible notes
Interest expense	438	2,784
Senior unsecured notes
Senior unsecured notes	1,603	0
Subordinated debentures
Subordinated debentures	459	457
Residential loans
Interest income	24,834	19,662
Consolidated SLST \| VIE, Primary Beneficiary
Interest income	9,380	10,318
Interest expense	5,978	7,104
Residential loans held in securitization trusts
Interest income	16,633	7,968
Total residential loans
Interest income	50,847	37,948
Multi-family loans
Interest income	2,951	4,401
Investment securities available for sale
Investment securities available for sale	4,675	7,675
Other
Other	28	15
Repurchase agreements
Interest expense	5,531	4,040
Residential loan securitizations
Interest expense	7,456	4,720
Non-Agency RMBS Re-Securitization
Interest expense	0	283
Total collateralized debt obligations
Interest expense	13,434	12,107
Mortgages payable on real estate
Mortgages payable on real estate	$ 7,157	$ 311

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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