Activity in the Allowance for Credit Losses (Detail) (USD $) In Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010		Mar. 31, 2011	Dec. 31, 2010	Mar. 31, 2010	Dec. 31, 2009
Balance at beginning of period	$ 2,908		$ 3,276		$ 3,032		$ 3,235
Provision for loan losses	395		702		846		1,579
Benefit for unfunded commitments	(3)		(40)		(7)		(55)
Loan charge-offs	(563)		(768)		(1,178)		(1,630)
Loan recoveries	58		46		102		87
Balance at end of period	2,795		3,216		2,795		3,216
Components:
ALLL	2,744		3,156		2,744		3,156		2,854	2,974	3,176	3,120
Unfunded commitments reserve	51	[1]	60	[1]	51	[1]	60	[1]
Allowance for credit losses	$ 2,795		$ 3,216		$ 2,795		$ 3,216

[1] The unfunded commitments reserve is separately recorded in other liabilities in the Consolidated Balance Sheets.