DERIVATIVE INSTRUMENTS - Summary of Characteristics of Interest Rate Swaps (Details) - Interest rate swaps, at fair value - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Current Notional	$ 55,145,571	$ 58,829,554
Weighted Average Pay Rate	3.05%	3.04%
Weighted Average Receive Rate	4.94%	5.31%
Weighted Average Years to Maturity	5 years 29 days	5 years 4 months 9 days
Federal funds index swap
Derivative [Line Items]
Notional amount, percentage	7.00%	6.00%
Secured Overnight Financing Rate
Derivative [Line Items]
Notional amount, percentage	93.00%	94.00%
0 - 3 years
Derivative [Line Items]
Minimum maturity period	0 years	0 years
Maximum maturity period	3 years	3 years
Current Notional	$ 19,961,229	$ 21,397,358
Weighted Average Pay Rate	3.33%	3.17%
Weighted Average Receive Rate	4.95%	5.26%
Weighted Average Years to Maturity	1 year 18 days	1 year 2 months 23 days
3 - 6 years
Derivative [Line Items]
Minimum maturity period	3 years	3 years
Maximum maturity period	6 years	6 years
Current Notional	$ 13,510,021	$ 12,461,799
Weighted Average Pay Rate	3.10%	3.09%
Weighted Average Receive Rate	4.94%	5.37%
Weighted Average Years to Maturity	4 years 7 months 13 days	4 years 9 months
6 - 10 years
Derivative [Line Items]
Minimum maturity period	6 years	6 years
Maximum maturity period	10 years	10 years
Current Notional	$ 20,114,937	$ 22,949,150
Weighted Average Pay Rate	2.77%	2.85%
Weighted Average Receive Rate	4.95%	5.34%
Weighted Average Years to Maturity	7 years 11 months 19 days	8 years 7 days
Greater than 10 years
Derivative [Line Items]
Minimum maturity period	10 years	10 years
Current Notional	$ 1,559,384	$ 2,021,247
Weighted Average Pay Rate	3.44%	3.53%
Weighted Average Receive Rate	4.84%	5.27%
Weighted Average Years to Maturity	23 years 6 months	22 years 8 months 15 days