REPURCHASE FACILITIES, CREDIT FACILITIES AND NOTES PAYABLE - Schedule of Repurchase Facilities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($) option	Dec. 31, 2021 USD ($)
Line of Credit Facility [Line Items]
Weighted Average Interest Rate	3.30%
Carrying Value of Loans Financed under Repurchase Facility	$ 3,911,239	$ 2,624,101
Minimum | One-Month LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.25%
Minimum | One-Month Term SOFR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.90%
Maximum | One-Month LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	2.15%
Maximum | One-Month Term SOFR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	2.75%
Deutsche Bank
Line of Credit Facility [Line Items]
Number of extension options | option	4
Extension period	1 year
J.P. Morgan | Minimum | One-Month Term SOFR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.20%
J.P. Morgan | Maximum | One-Month Term SOFR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.35%
Citibank, Barclays And Wells Fargo
Line of Credit Facility [Line Items]
Number of extension options | option	2
Extension period	1 year
Credit facilities | Affiliated Entity
Line of Credit Facility [Line Items]
Maximum Facility Size	$ 2,700,000
Amount Financed	2,150,994
Credit facilities | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	2,875,177
Credit facilities | Citibank | Affiliated Entity
Line of Credit Facility [Line Items]
Maximum Facility Size	$ 400,000
Weighted Average Interest Rate	3.00%
Amount Financed	$ 329,153
Credit facilities | Citibank | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	456,225
Credit facilities | Barclays | Affiliated Entity
Line of Credit Facility [Line Items]
Maximum Facility Size	$ 1,250,000
Weighted Average Interest Rate	3.10%
Amount Financed	$ 912,598
Credit facilities | Barclays | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	1,158,109
Credit facilities | Wells Fargo | Affiliated Entity
Line of Credit Facility [Line Items]
Maximum Facility Size	$ 750,000
Weighted Average Interest Rate	2.90%
Amount Financed	$ 690,810
Credit facilities | Wells Fargo | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	881,515
Credit facilities | Deutsche Bank | Affiliated Entity
Line of Credit Facility [Line Items]
Maximum Facility Size	$ 300,000
Weighted Average Interest Rate	3.50%
Amount Financed	$ 143,023
Credit facilities | Deutsche Bank | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	$ 186,253
Credit facilities | J.P. Morgan | Affiliated Entity
Line of Credit Facility [Line Items]
Weighted Average Interest Rate	2.50%
Amount Financed	$ 75,410
Credit facilities | J.P. Morgan | Affiliated Entity | Senior Loan
Line of Credit Facility [Line Items]
Carrying Value of Loans Financed under Repurchase Facility	$ 193,075