ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 23,585	$ 24,328	$ 23,690	$ 23,420
Other comprehensive income (loss) before reclassifications	(826)	(1,641)	(1,070)	(4,166)
Amounts reclassified to the Consolidated Statements of Operations	146	36	387	8
Total other comprehensive income (loss), net of income taxes	(680)	(1,605)	(683)	(4,158)
Ending balance	22,878	23,146	22,878	23,146
Total AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(4,563)	(3,218)	(4,560)	(665)
Total other comprehensive income (loss), net of income taxes	(680)	(1,605)	(683)	(4,158)
Ending balance	(5,243)	(4,823)	(5,243)	(4,823)
Net Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(1,553)	(862)	(1,416)	(161)
Other comprehensive income (loss) before reclassifications	(248)	(738)	(580)	(1,407)
Amounts reclassified to the Consolidated Statements of Operations	120	34	315	2
Total other comprehensive income (loss), net of income taxes	(128)	(704)	(265)	(1,405)
Ending balance	(1,681)	(1,566)	(1,681)	(1,566)
Net Unrealized Gains (Losses) on Debt Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(2,643)	(2,016)	(2,771)	(156)
Other comprehensive income (loss) before reclassifications	(578)	(903)	(490)	(2,759)
Amounts reclassified to the Consolidated Statements of Operations	23	0	63	(4)
Total other comprehensive income (loss), net of income taxes	(555)	(903)	(427)	(2,763)
Ending balance	(3,198)	(2,919)	(3,198)	(2,919)
Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(367)	(340)	(373)	(348)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified to the Consolidated Statements of Operations	3	2	9	10
Total other comprehensive income (loss), net of income taxes	3	2	9	10
Ending balance	$ (364)	$ (338)	$ (364)	$ (338)