Certain Transfers of Financial Assets and Variable Interest Entities Tax Credit Variable Interest Entities (Details) - USD ($) $ in Millions		Dec. 31, 2018	Dec. 31, 2017
Other Assets	[1],[2]	$ 8,991	$ 9,099
Community Development Investments [Member]
Other Assets	[3]	1,636	1,272
Community Development Investments [Member] | Limited Partner [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	[4]	2,207	1,905
Renewable Energy Program [Member]
Other Assets		86	0
Renewable Energy Program [Member] | Limited Partner [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	[4]	$ 138	$ 0

[1] Beginning January 1, 2018, the Company reclassified equity securities previously presented in Securities available for sale to Other assets. Reclassifications have been made to previously reported amounts for comparability.

[2] Beginning October 1, 2018, the Company reclassified software and related accumulated amortization previously presented in Other assets to Premises, property, and equipment, net. Reclassifications have been made to previously reported amounts for comparability.

[3] At December 31, 2018 and 2017, the carrying value of community development investments excludes $68 million and $59 million of investments in funds that do not qualify for tax credits, respectively.

[4] At December 31, 2018 and 2017, the Company's maximum exposure to loss related to community development investments includes $422 million and $354 million of loans and $639 million and $627 million of unfunded equity commitments, respectively. At December 31, 2018, the Company's maximum exposure to loss related to renewable energy partnerships includes $52 million of unfunded equity commitments.