GOVERNMENT AND GOVERNMENT-BACKED SECURITIES - Schedule of Agency and Treasury Securities by Designation (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($) security	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items]
Weighted Average Life (Years)	4 years
Agency
Debt Securities, Available-for-sale [Line Items]
Outstanding Face Amount	$ 9,561,293
Gross unrealized gains	3,291
Gross unrealized losses	(66,040)
Carrying value	$ 9,300,237	$ 8,533,130
Number of Securities | security	47
Weighted Average Coupon	5.60%
Weighted average yield	8.00%
Weighted Average Life (Years)	8 years 7 months 6 days
Securities designated as available for sale (“AFS”):
Debt Securities, Available-for-sale [Line Items]
Outstanding Face Amount	$ 71,981
Gross unrealized gains	0
Gross unrealized losses	0
Carrying value	$ 62,998	65,496
Number of Securities | security	1
Weighted Average Coupon	3.50%
Weighted average yield	3.50%
Weighted Average Life (Years)	10 years 8 months 12 days
Securities measured at fair value through net income:
Debt Securities, Available-for-sale [Line Items]
Outstanding Face Amount	$ 9,489,312
Gross unrealized gains	3,291
Gross unrealized losses	(66,040)
Carrying value	$ 9,237,239	$ 8,467,634
Number of Securities | security	46
Weighted Average Coupon	5.10%
Weighted average yield	5.20%
Weighted Average Life (Years)	8 years 8 months 12 days