Deferred Income Taxes Included in Other Assets in the Consolidated Balance Sheets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Deferred Income Tax Assets And Liabilities [Line Items]
Allowance for loan & lease losses	$ 789	$ 1,051
Deferred compensation	119	136
Impairment reserves	102	144
Reserves	70	52
Reserve for unfunded commitments	63	79
State net operating losses	63	66
Other	216	221
Total deferred tax assets	1,422	1,749
Lease financing	853	801
Investments in joint ventures and partnership interests	468	481
Other comprehensive income	253	169
MSRs	173	190
Bank premises and equipment	95	69
State deferred taxes	74	53
Other	130	130
Total deferred tax liabilities	2,046	1,893
Total net deferred tax (liability) asset	$ (624)	$ (144)