Segments (Results of Operations and Average Assets by Segment) (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting Information
Bank premises impairment	$ 20	$ 8
Other asset impairment charges	0	(2)
Bank premises and equipment held for sale	78		$ 42
Commercial Banking \| Operating lease equipment
Segment Reporting Information
Other asset impairment charges		2
General Corporate and Other
Segment Reporting Information
Bank premises and equipment held for sale	$ 78	$ 20

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

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