Loans and Related Allowance for Credit Losses (Financial Impact and TDRs by Concession Type) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	10,866
Pre-TDR Recorded Investment	$ 525
Post-TDR Recorded Investment	414
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	9
Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	181
Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	$ 224
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	57
Pre-TDR Recorded Investment	$ 363
Post-TDR Recorded Investment	269
Commercial | Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	9
Commercial | Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	58
Commercial | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	$ 202
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	10,809
Pre-TDR Recorded Investment	$ 162
Post-TDR Recorded Investment	145
Consumer | Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment
Consumer | Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	123
Consumer | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-TDR Recorded Investment	$ 22