Goodwill and Mortgage Servicing Rights - by Business Segment (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Total goodwill	$ 47,471	$ 47,507	$ 47,288	$ 47,325
Consumer & Community Banking
Goodwill [Line Items]
Total goodwill	30,984	31,013	30,797
Corporate & Investment Bank
Goodwill [Line Items]
Total goodwill	6,770	6,776	6,772
Commercial Banking
Goodwill [Line Items]
Total goodwill	2,860	2,860	2,861
Asset & Wealth Management
Goodwill [Line Items]
Total goodwill	$ 6,857	$ 6,858	$ 6,858