Premises and Equipment (Schedule of Premises and Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 4,638	$ 4,610
Accumulated depreciation and amortization	(2,824)	(2,713)
Premises and equipment, net	1,814	1,897
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	419	434
Premises and improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	1,651	1,678
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	1,056	1,041
Software
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	926	836
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	434	413
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 152	$ 208

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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