LOANS - Summary of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Interest income	$ 475,140	$ 322,859	$ 1,056,068	$ 1,010,264
Total included in net income (loss)	866,696	(295,642)	2,888,951	1,455,171
Residential Mortgage Loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Interest income	91,645	38,963	165,110	76,072
Net gains (losses) on disposal of investments	(5,321)	(21,721)	(12,658)	(26,941)
Net unrealized gains (losses) on instruments measured at fair value through earnings	(324,481)	14,456	(739,729)	36,911
Total included in net income (loss)	$ (238,157)	$ 31,698	$ (587,277)	$ 86,042