Net Interest Income - Schedule of Components of Interest Income and Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest income	$ 65,195	$ 68,920	$ 179,871	$ 195,441
Interest expense	48,406	38,563	130,145	88,767
Total net interest income	16,789	30,357	49,726	106,674
Convertible notes
Interest expense	0	0	0	438
Senior unsecured notes
Senior unsecured notes	1,620	1,608	4,852	4,818
Subordinated debentures
Subordinated debentures	1,078	704	3,063	1,713
Residential loans
Interest income	11,574	32,374	40,817	89,875
Consolidated SLST \| VIE, Primary Beneficiary
Interest income	8,370	9,013	25,543	27,648
Interest expense	5,957	6,611	18,238	18,796
Residential loans held in securitization trusts
Interest income	24,183	20,437	74,041	55,923
Total residential loans
Interest income	44,127	61,824	140,401	173,446
Multi-family loans
Interest income	2,712	2,862	7,890	8,646
Investment securities available for sale
Investment securities available for sale	17,203	3,916	27,862	12,922
Other
Other	1,153	318	3,718	427
Repurchase agreements
Interest expense	24,169	18,448	54,084	35,625
Residential Loan Securitizations
Interest expense	15,582	11,192	49,908	27,377
Total collateralized debt obligations
Interest expense	$ 21,539	$ 17,803	$ 68,146	$ 46,173

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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