Activity Related to the MSR Portfolio (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Servicing Assets at Fair Value
Securities gains, net - non-qualifying hedges on MSRs	$ 13	$ 3	$ 9
Changes in fair value and settlement of free-standing derivatives purchased to economically hedge the MSR portfolio (Mortgage banking net revenue)	(30)	63	344
Recovery of (provision for) MSR impairment (Mortgage banking net revenue)	$ 192	$ (103)	$ (242)