SECURITIES - Summary of Residential Securities and CMBS (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2025 USD ($)
Debt Securities, Available-For-Sale [Roll Forward]
Beginning balance January 1, 2025	$ 69,756,447	[1],[2]
Purchases	6,364,320
Sales	(5,194,416)
Principal paydowns	(1,671,819)
(Amortization) / accretion	(57,430)
Fair value adjustment	1,164,262
Ending balance March 31, 2025	70,361,364	[2]
Agency Securities
Debt Securities, Available-For-Sale [Roll Forward]
Beginning balance January 1, 2025	67,434,068
Purchases	6,263,002
Sales	(4,967,149)
Principal paydowns	(1,516,963)
(Amortization) / accretion	(56,057)
Fair value adjustment	1,172,819
Ending balance March 31, 2025	68,329,720
Residential Credit Securities
Debt Securities, Available-For-Sale [Roll Forward]
Beginning balance January 1, 2025	2,248,101
Purchases	101,318
Sales	(214,381)
Principal paydowns	(152,573)
(Amortization) / accretion	(1,356)
Fair value adjustment	(8,526)
Ending balance March 31, 2025	1,972,583
Commercial Securities
Debt Securities, Available-For-Sale [Roll Forward]
Beginning balance January 1, 2025	74,278
Purchases	0
Sales	(12,886)
Principal paydowns	(2,283)
(Amortization) / accretion	(17)
Fair value adjustment	(31)
Ending balance March 31, 2025	$ 59,061

[1] (1)Derived from the audited consolidated financial statements at December 31, 2024.

[2] (3)Excludes $2.3 billion and $2.2 billion at March 31, 2025 and December 31, 2024, respectively, of non-Agency mortgage-backed securities in consolidated VIEs pledged as collateral and eliminated from the Company’s Consolidated Statements of Financial Condition.