Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 199	$ 224
Accumulated Amortization	(180)	(197)
Net Carrying Amount	19	27
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	154	180
Accumulated Amortization	(141)	(160)
Net Carrying Amount	13	20
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	45	44
Accumulated Amortization	(39)	(37)
Net Carrying Amount	$ 6	$ 7