VARIABLE INTEREST ENTITIES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Variable Interest Entity [Line Items]
Securitized debt of consolidated VIEs	$ 15,831,915		$ 15,831,915		$ 11,600,338	[1]
Costs incurred in connection with securitization	44,891	$ 42,915	83,461	$ 83,743
Securitized debt of consolidated VIE, unrealized gain (loss)	4,800	90,800	130,500	(81,400)
Participations issued	1,144,821		1,144,821		1,103,835	[1]
Consolidated VIEs
Variable Interest Entity [Line Items]
Exposure to obligations of VIEs	1,900,000		1,900,000
Securitized debt of consolidated VIEs	15,800,000		15,800,000		11,600,000
Costs incurred in connection with securitization	5,300	$ 2,700
Contractual principal amount of debt held by third parties	16,900,000		16,900,000		12,600,000
Consolidated VIEs | OBX Trust
Variable Interest Entity [Line Items]
Costs incurred in connection with securitization			9,100	$ 4,000
Consolidated VIEs | Consolidation, Eliminations
Variable Interest Entity [Line Items]
Mortgage-backed securities	1,900,000		1,900,000		1,400,000
VIE, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Participations issued	$ 1,100,000		$ 1,100,000		$ 1,100,000

[1] (1)Derived from the audited consolidated financial statements at December 31, 2023.