Activity Related to the MSR Portfolio (Detail) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Servicing Assets at Fair Value [Line Items]
Securities gains, net - non-qualifying hedges on MSRs			$ 5
Changes in fair value and settlement of free-standing derivatives purchased to economically hedge the MSR portfolio (Mortgage banking net revenue)	129	96	102	154
Provision for MSR impairment (Mortgage banking net revenue)	$ (64)	$ (100)	$ (27)	$ (106)