ALLOWANCE FOR LOAN AND LEASE LOSSES - Schedule of Allowance for Loan and Lease Losses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning balance	$ 1,672	$ 1,700	$ 1,676	$ 1,747
Provision (benefit) for loan and lease losses	214	123	473	311
Charge-offs	(256)	(177)	(567)	(464)
Recoveries	22	32	70	84
Allowance for loan and lease losses, ending balance	1,652	1,678	1,652	1,678
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning balance	1,512	1,547	1,518	1,581
Provision (benefit) for loan and lease losses	238	123	487	316
Charge-offs	(244)	(169)	(540)	(443)
Recoveries	18	27	59	74
Allowance for loan and lease losses, ending balance	1,524	1,528	1,524	1,528
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning balance	160	153	158	166
Provision (benefit) for loan and lease losses	(24)	0	(14)	(5)
Charge-offs	(12)	(8)	(27)	(21)
Recoveries	4	5	11	10
Allowance for loan and lease losses, ending balance	$ 128	$ 150	$ 128	$ 150