RESIDENTIAL MORTGAGE LOANS - Residential Mortgage Loans Outstanding by Loan Type, Excluding REO (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($) loan	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount		$ 35,000
Weighted Average Life (Years)	4 years
Investments of consolidated CFEs
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 3,156,142
Carrying Value	$ 3,051,688		$ 2,791,027
Loan Count | loan	8,025
Weighted Average Yield	6.00%
Weighted Average Life (Years)	25 years 8 months 12 days
Residential mortgage loans, HFI, at fair value
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 360,448
Carrying Value	$ 334,589		361,890
Loan Count | loan	6,836
Weighted Average Yield	7.70%
Weighted Average Life (Years)	4 years 7 months 6 days
Total Residential Mortgage Loans, HFS
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 65,743
Carrying Value	$ 58,791		66,670
Loan Count | loan	1,724
Weighted Average Yield	7.50%
Weighted Average Life (Years)	4 years 3 months 18 days
Acquired performing loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 50,718
Carrying Value	$ 46,458		51,011
Loan Count | loan	1,543
Weighted Average Yield	6.60%
Weighted Average Life (Years)	4 years 3 months 18 days
Acquired performing loans | Ginnie Mae
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	$ 236,800
Acquired non-performing loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	15,025
Carrying Value	$ 12,333		15,659
Loan Count | loan	181
Weighted Average Yield	10.60%
Weighted Average Life (Years)	4 years 3 months 18 days
Acquired non-performing loans | Ginnie Mae
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	$ 234,100
Total Residential Mortgage Loans, HFS, at Fair Value
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	5,763,203
Carrying Value	$ 5,888,611		4,307,571
Loan Count | loan	17,689
Weighted Average Yield	6.40%
Weighted Average Life (Years)	23 years 3 months 18 days
Acquired performing loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 1,657,670
Carrying Value	$ 1,694,140		408,421
Loan Count | loan	4,049
Weighted Average Yield	6.20%
Weighted Average Life (Years)	9 years 8 months 12 days
Acquired non-performing loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 244,650
Carrying Value	$ 222,502		270,879
Loan Count | loan	1,063
Weighted Average Yield	5.20%
Weighted Average Life (Years)	27 years 6 months
Originated loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Outstanding Face Amount	$ 3,860,883
Carrying Value	$ 3,971,969		$ 3,628,271
Loan Count | loan	12,577
Weighted Average Yield	6.60%
Weighted Average Life (Years)	28 years 10 months 24 days