Loans and Leases - Accruing And Non-Accruing Loans By Class (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	$ 54,436	$ 57,730
Total Accruing	54,584	57,847
Current, Non-Accruing	182	205
Total Non-Accruing	275	386
Loans and leases	54,859	58,232
30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	108	100
Past Due, Non-Accruing	7	66
90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	40	17
Past Due, Non-Accruing	86	115
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	31,068	33,104
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	30,885	32,945
Total Accruing	30,943	32,960
Current, Non-Accruing	97	88
Total Non-Accruing	125	144
Loans and leases	31,068	33,104
Commercial | Commercial and industrial | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	53	15
Past Due, Non-Accruing	1	12
Commercial | Commercial and industrial | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	5	0
Past Due, Non-Accruing	27	44
Commercial | Commercial and industrial | C&I (a)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	26,367	27,541
Total Accruing	26,425	27,556
Current, Non-Accruing	97	88
Total Non-Accruing	125	144
Loans and leases	26,550	27,700
Nonaccrual, no allowance	99	101
Commercial | Commercial and industrial | C&I (a) | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	53	15
Past Due, Non-Accruing	1	12
Commercial | Commercial and industrial | C&I (a) | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	5	0
Past Due, Non-Accruing	27	44
Commercial | Commercial and industrial | Loans to mortgage companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	4,518	5,404
Total Accruing	4,518	5,404
Current, Non-Accruing	0	0
Total Non-Accruing	0	0
Loans and leases	4,518	5,404
Commercial | Commercial and industrial | Loans to mortgage companies | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	0	0
Past Due, Non-Accruing	0	0
Commercial | Commercial and industrial | Loans to mortgage companies | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	0	0
Past Due, Non-Accruing	0	0
Commercial | Commercial and industrial | CRE (b)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual, no allowance	5
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	12,109	12,275
Commercial | Commercial real estate | CRE (b)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	12,087	12,194
Total Accruing	12,100	12,217
Current, Non-Accruing	6	10
Total Non-Accruing	9	58
Loans and leases	12,109	12,275
Commercial | Commercial real estate | CRE (b) | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	13	23
Past Due, Non-Accruing	1	42
Commercial | Commercial real estate | CRE (b) | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	0	0
Past Due, Non-Accruing	2	6
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	10,772	11,725
Consumer | Consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	10,564	11,474
Total Accruing	10,634	11,543
Current, Non-Accruing	78	106
Total Non-Accruing	138	182
Loans and leases	10,772	11,725
Consumer | Consumer real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	37	53
Past Due, Non-Accruing	5	12
Consumer | Consumer real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	33	16
Past Due, Non-Accruing	55	64
Consumer | Consumer real estate | HELOC (c)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	1,906	2,336
Total Accruing	1,919	2,360
Current, Non-Accruing	34	43
Total Non-Accruing	45	60
Loans and leases	1,964	2,420
Nonaccrual, no allowance	7
Consumer | Consumer real estate | HELOC (c) | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	7	13
Past Due, Non-Accruing	2	3
Consumer | Consumer real estate | HELOC (c) | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	6	11
Past Due, Non-Accruing	9	14
Consumer | Consumer real estate | Real estate installment loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	8,658	9,138
Total Accruing	8,715	9,183
Current, Non-Accruing	44	63
Total Non-Accruing	93	122
Loans and leases	8,808	9,305
Nonaccrual, no allowance	50
Consumer | Consumer real estate | Real estate installment loans | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	30	40
Past Due, Non-Accruing	3	9
Consumer | Consumer real estate | Real estate installment loans | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	27	5
Past Due, Non-Accruing	46	50
Consumer | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	900	1,117
Total Accruing	907	1,127
Current, Non-Accruing	1	1
Total Non-Accruing	3	2
Loans and leases	910	1,128
Consumer | Credit Card and Other | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	5	9
Past Due, Non-Accruing	0	0
Consumer | Credit Card and Other | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	2	1
Past Due, Non-Accruing	2	1
Consumer | Credit Card and Other | Credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	292	279
Total Accruing	296	283
Current, Non-Accruing	0	0
Total Non-Accruing	0	0
Loans and leases	296	283
Consumer | Credit Card and Other | Credit card | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	2	3
Past Due, Non-Accruing	0	0
Consumer | Credit Card and Other | Credit card | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	2	1
Past Due, Non-Accruing	0	0
Consumer | Credit Card and Other | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, Accruing	608	838
Total Accruing	611	844
Current, Non-Accruing	1	1
Total Non-Accruing	3	2
Loans and leases	614	845
Consumer | Credit Card and Other | Other | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	3	6
Past Due, Non-Accruing	0	0
Consumer | Credit Card and Other | Other | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due, Accruing	0	0
Past Due, Non-Accruing	$ 2	$ 1