SECURED FINANCING - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Repurchase Agreements:
Repurchase agreements	$ 59,512,597	$ 54,769,643
Repurchase agreements - weighted average remaining maturities	27 days	52 days
Repurchase agreement amount	$ 1,800,000
Remaining capacity of repurchase agreement	1,100,000
Other secured financing	$ 250,000	$ 903,255
Debt weighted average interest rate	7.07%
Secured financings and interest rate swaps - collateral held, estimated fair value	$ 62,200,000	59,200,000
Secured financings and interest rate swaps - collateral held, accrued interest	$ 226,400	$ 160,800
Minimum
Repurchase Agreements:
Debt Instrument, Maturity	1 year
Maximum
Repurchase Agreements:
Debt Instrument, Maturity	3 years
Mortgage Servicing Rights Committed Credit Facility | Line of Credit
Repurchase Agreements:
Credit facility, maximum borrowing capacity	$ 500,000