Asset Quality - Allowance for Loan and Lease Losses (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Balance at beginning of period - continuing operations	$ 1,004	$ 1,604	$ 2,534
Charge-offs	(508)	(715)	(1,822)
Recoveries	163	174	252
Net loans and leases charged off	(345)	(541)	(1,570)
Provision for loan and lease losses from continuing operations	229	(60)	638
Foreign currency translation adjustment		1	2
Balance at end of period - continuing operations	$ 888	$ 1,004	$ 1,604