Summary of Transactions in the ALLL (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Beginning Balance	$ (3,004)	[1]	$ (3,749)		$ (2,787)
Impact of change in accounting principle			45
Losses charged off	(1,314)		(2,485)		(2,719)
Recoveries of losses previously charged off	142		157		138
Provision for loan and lease losses	423		1,538		3,543
Ending Balance	$ 2,255	[1]	$ 3,004	[1]	$ 3,749

[1] At December 31, 2011 and 2010, includes $30 and $52 of cash, $7 of other short-term investments, $50 and $29 of commercial mortgage loans, $223 and $241 of home equity loans, $259 and $648 of automobile loans, ($10) and ($14) of ALLL, $4 and $7 of other assets, $4 and $12 of other liabilities, $191 and $692 of long-term debt from consolidated VIEs that are included in their respective captions. See Note 11.