Total Gains and Losses Included in Earnings for Assets and Liabilites Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses included in earnings	$ 233	$ 440	$ 166
Mortgage Banking Revenue [Member] | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses included in earnings	57	418	210
Other Noninterest Income [Member] | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses included in earnings	175	21	(46)
Corporate Banking Revenue [Member] | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses included in earnings	$ 1	$ 1	$ 2