Allowance for Credit Losses - Gross Charge-Offs by Year of Origination - Prior Year (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Allowance for Loan and Lease Losses [Roll Forward]
2024	$ 10	$ 9	$ 13
2023	5	18	19
2022	16	21	82
2021	33	23	5
2020	32	20	12
Prior to 2020	48	53	54
Revolving Loans	22	13	14
Total	166	157	199
Commercial | C&I
Allowance for Loan and Lease Losses [Roll Forward]
2024	3	1	1
2023	5	16	17
2022	13	15	82
2021	22	23	5
2020	30	3	10
Prior to 2020	39	15	34
Revolving Loans	14	4	7
Total	126	77	156
Commercial | CRE
Allowance for Loan and Lease Losses [Roll Forward]
2024	0	0	0
2023	0	0	0
2022	0	5	0
2021	9	0	0
2020	0	17	2
Prior to 2020	6	34	15
Revolving Loans	0	0	0
Total	15	56	17
Consumer | Credit card and other:
Allowance for Loan and Lease Losses [Roll Forward]
2024	7	8	12
2023	0	1	1
2022	1	1	0
2021	1	0	0
2020	2	0	0
Prior to 2020	1	2	2
Revolving Loans	8	9	7
Total	$ 20	$ 21	$ 22