Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Segments (Results of Operations and Average Assets by Segment) (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting Information
Other Asset Impairment Charges	$ (2)	$ (20)
Bank premises and equipment held for sale	20		$ 27
Branch Banking
Segment Reporting Information
Impairment of Branches and Land	8	3
Commercial Banking \| Operating lease equipment
Segment Reporting Information
Other Asset Impairment Charges		31
General Corporate and Other
Segment Reporting Information
Bank premises and equipment held for sale	$ 20	$ 51