Loans and Related Allowance for Credit Losses (Financial Impact and TDRs by Concession Type) (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2022 USD ($) customer	Sep. 30, 2022 USD ($) customer
Financing Receivable [Line Items]
Number of Loans | customer	2,247	8,194
Pre-TDR Amortized Cost Basis	$ 136	$ 310
Post-TDR Amortized Cost Basis	112	267
Principal Forgiveness
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis		9
Interest Rate Reduction
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	39	105
Other
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	$ 73	$ 153
Total commercial
Financing Receivable [Line Items]
Number of Loans | customer	15	42
Pre-TDR Amortized Cost Basis	$ 96	$ 184
Post-TDR Amortized Cost Basis	77	154
Total commercial | Principal Forgiveness
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis		9
Total commercial | Interest Rate Reduction
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	10	10
Total commercial | Other
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	$ 67	$ 135
Total consumer
Financing Receivable [Line Items]
Number of Loans | customer	2,232	8,152
Pre-TDR Amortized Cost Basis	$ 40	$ 126
Post-TDR Amortized Cost Basis	35	113
Total consumer | Principal Forgiveness
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis
Total consumer | Interest Rate Reduction
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	29	95
Total consumer | Other
Financing Receivable [Line Items]
Post-TDR Amortized Cost Basis	$ 6	$ 18