Fee-based Revenue from Contracts with Customers - Asset Management Group Noninterest Income Disaggregation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Noninterest Income	$ 7,411	$ 7,221	$ 6,771
Asset Management Group
Disaggregation of Revenue [Line Items]
Noninterest Income	892	$ 881	$ 851
Asset Management Group | In-Scope Asset Management Group Noninterest Income [Member]
Disaggregation of Revenue [Line Items]
Noninterest Income	883
Asset Management Group | Out-of-Scope Asset Management Group Noninterest Income [Member]
Disaggregation of Revenue [Line Items]
Noninterest Income	9
Asset Management Group | Personal [Member] | In-Scope Asset Management Group Noninterest Income [Member]
Disaggregation of Revenue [Line Items]
Noninterest Income	611
Asset Management Group | Institutional [Member] | In-Scope Asset Management Group Noninterest Income [Member]
Disaggregation of Revenue [Line Items]
Noninterest Income	$ 272