Derivative Positions (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified									1 Months Ended		3 Months Ended
	Mar. 31, 2012 Nondesignated Trading Activity	Dec. 31, 2011 Nondesignated Trading Activity	Mar. 31, 2012 Derivative Financial Instruments, Assets Nondesignated Trading Activity	Dec. 31, 2011 Derivative Financial Instruments, Assets Nondesignated Trading Activity	Mar. 31, 2012 Derivative Financial Instruments, Assets Nondesignated Future	Dec. 31, 2011 Derivative Financial Instruments, Assets Nondesignated Future	Mar. 31, 2012 Derivative Financial Instruments, Liabilities [Member] Nondesignated	Mar. 31, 2012 Derivative Financial Instruments, Liabilities [Member] Nondesignated Future	May 31, 2009 Derivative Financial Instruments, Liabilities [Member] Visa Interest Nondesignated	Dec. 31, 2011 Nondesignated	Mar. 31, 2012 Cash Flow Hedging	Mar. 31, 2011 Cash Flow Hedging	Mar. 31, 2012 Cash Flow Hedging Interest Income (Expense), Net [Member]	Mar. 31, 2011 Cash Flow Hedging Interest Income (Expense), Net [Member]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net											$ 83	$ 113	$ 69	$ 41
Notional amounts related to interest rate futures			16,900	16,700	1,095			171
Notional related to equity futures			1,000	600		1,203
Asset amount notional from purchased and written interest rate swap risk participation agreements	2	2
Liability amount notional from purchased and written interest rate swap risk participation agreements	6	6
Derivative liability recorded in other liabilities, established upon the sale of Visa Class B shares							4.9			22.0
Notional amount, established upon the sale of Visa Class B shares							$ 134			$ 134
Shares of Class B Visa Inc. common stock sold to another financial institution, shares									3.2