Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill by Reportable Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill	$ 6,337	$ 6,337
Goodwill, Acquired During Period	0
Consumer Banking and Private Wealth Management [Member]
Goodwill [Line Items]
Goodwill	4,262	4,262
Goodwill, Acquired During Period	0
Wholesale Banking [Member]
Goodwill [Line Items]
Goodwill	2,075	$ 2,075
Goodwill, Acquired During Period	$ 0