Label	Element	Value
Common Stock [Member]
Common Stock, Shares, Outstanding	us-gaap_CommonStockSharesOutstanding	433,000,000
Common Stock, Shares, Outstanding	us-gaap_CommonStockSharesOutstanding	457,000,000
Cumulative Effect, Period Of Adoption, Adjusted Balance [Member]
Financing Receivable, Allowance for Credit Loss	us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 3,205,000,000
Cumulative Effect, Period Of Adoption, Adjusted Balance [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	us-gaap_FinancingReceivableAllowanceForCreditLosses	1,508,000,000
Cumulative Effect, Period Of Adoption, Adjusted Balance [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	us-gaap_FinancingReceivableAllowanceForCreditLosses	1,697,000,000
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period Of Adoption, Adjustment [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	us-gaap_FinancingReceivableAllowanceForCreditLosses	(304,000,000)
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period Of Adoption, Adjustment [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 767,000,000