MORTGAGE SERVICING RIGHTS AND MSR FINANCING RECEIVABLES - Schedule of Investment in MSRs (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2023	Dec. 31, 2022
Servicing Asset at Amortized Cost [Line Items]
Weighted Average Life (Years)		1 year
Fair value		$ 8,694,868	$ 8,889,403
Residential mortgage loan repurchase liability	[1]	1,443,546	$ 1,219,890
Mortgage Servicing Rights and Mortgage Servicing Rights Financing Receivable
Servicing Asset at Amortized Cost [Line Items]
UPB of Underlying Residential Mortgage Loans		$ 530,921,220
Weighted Average Life (Years)		7 years 10 months 24 days
Fair value		$ 8,694,868
MSRs | Weighted Average
Servicing Asset at Amortized Cost [Line Items]
Discount rate		8.50%
MSRs | Minimum
Servicing Asset at Amortized Cost [Line Items]
Discount rate		7.90%
MSRs | Maximum
Servicing Asset at Amortized Cost [Line Items]
Discount rate		10.80%
Agency | MSRs
Servicing Asset at Amortized Cost [Line Items]
UPB of Underlying Residential Mortgage Loans		$ 354,510,758
Weighted Average Life (Years)		8 years 1 month 6 days
Fair value		$ 5,393,329
Non-Agency | MSRs
Servicing Asset at Amortized Cost [Line Items]
UPB of Underlying Residential Mortgage Loans		$ 50,056,162
Weighted Average Life (Years)		6 years 10 months 24 days
Fair value		$ 704,873
Ginnie Mae | MSRs
Servicing Asset at Amortized Cost [Line Items]
UPB of Underlying Residential Mortgage Loans		$ 126,354,300
Weighted Average Life (Years)		7 years 8 months 12 days
Fair value		$ 2,596,666

[1] See Note 5 for details.