Impacts of Derivative Financial Instruments on the Consolidated Statements of Income/(Loss) and the Consolidated Statements of Shareholders' Equity (Parenthetical) (Detail) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011	Jun. 30, 2012		Jun. 30, 2011
Cash Flow Hedging
Reclassified in pre-tax gains from AOCI into net interest income	$ 83,000,000		$ 105,000,000	$ 166,000,000		$ 218,000,000
Derivative Instruments, Gain (Loss) Recognized in Income, Net	8,000,000	[1]		8,000,000	[1]
Cash Flow Hedging | Interest Income (Expense), Net [Member]
Reclassified in pre-tax gains from AOCI into net interest income	37,000,000		49,000,000	105,000,000		90,000,000
Nondesignated
Derivative Instruments, Gain (Loss) Recognized in Income, Net	557,000,000		181,000,000	686,000,000		239,000,000
Loans | Credit Risk Contract [Member] | Nondesignated | Trading Account Profits And Commissions [Member]
Derivative Instruments, Gain (Loss) Recognized in Income, Net			$ 0	$ 3,000,000		$ (1,000,000)

[1] Amounts are recognized in trading income in the Consolidated Statements of Income.