Bank Premises and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 245	$ 233	$ 224
Rental income from leased premises	16	17	19
Bank premises and equipment impairment	(6)	(21)
Other noninterest income	other noninterest income
Cancelable And Noncancelable Lease Obligations
Property, Plant and Equipment [Line Items]
Occupancy Costs	$ 98	$ 99	$ 99