Loans and Related Allowance for Credit Losses, Payment Performance of Consumer Loan Modifications (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Total Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-offs	$ 11	$ 27	$ 106	$ 42
Accounts, Notes, Loans and Financing Receivable Textual [Abstract]
Loans modified, commitment to lend additional funds			317	167
Total Commercial [Member] | Excluding modifications in payment deferral period member [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	2,867	755	2,867	755
Total Commercial [Member] | Excluding modifications in payment deferral period member [Member] | Current-29 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	2,674	724	2,674	724
Total Commercial [Member] | Excluding modifications in payment deferral period member [Member] | 30-89 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	56	29	56	29
Total Commercial [Member] | Excluding modifications in payment deferral period member [Member] | 90 days or more past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	137	2	137	2
Total Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-offs	57	26	145	52
Accounts, Notes, Loans and Financing Receivable Textual [Abstract]
Loans modified during the period, subsequent default	96	130	171	251
Total Consumer [Member] | Excluding modifications in payment deferral period member [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	1,386	996	1,386	996
Total Consumer [Member] | Excluding modifications in payment deferral period member [Member] | Current-29 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	978	638	978	638
Total Consumer [Member] | Excluding modifications in payment deferral period member [Member] | 30-89 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	236	132	236	132
Total Consumer [Member] | Excluding modifications in payment deferral period member [Member] | 90 days or more past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	172	226	172	226
Total Consumer [Member] | Residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-offs	0	1	5	7
Total Consumer [Member] | Residential mortgage [Member] | Excluding modifications in payment deferral period member [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	636	648	636	648
Total Consumer [Member] | Residential mortgage [Member] | Excluding modifications in payment deferral period member [Member] | Current-29 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	411	377	411	377
Total Consumer [Member] | Residential mortgage [Member] | Excluding modifications in payment deferral period member [Member] | 30-89 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	127	80	127	80
Total Consumer [Member] | Residential mortgage [Member] | Excluding modifications in payment deferral period member [Member] | 90 days or more past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	98	191	98	191
Total Consumer [Member] | Credit card [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-offs	57	25	140	45
Total Consumer [Member] | Credit card [Member] | Excluding modifications in payment deferral period member [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	750	348	750	348
Total Consumer [Member] | Credit card [Member] | Excluding modifications in payment deferral period member [Member] | Current-29 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	567	261	567	261
Total Consumer [Member] | Credit card [Member] | Excluding modifications in payment deferral period member [Member] | 30-89 days past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	109	52	109	52
Total Consumer [Member] | Credit card [Member] | Excluding modifications in payment deferral period member [Member] | 90 days or more past due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified during the period	$ 74	$ 35	$ 74	$ 35