Premises and Equipment - Capital and Noncancelable Operating Leases (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Leases Disclosure [Line Items]
2012	$ 214
2013	205
2014	194
2015	177
2016	169
Thereafter	509
Total minimum lease payments	1,468
2012	2
2013	2
2014	2
2015	2
2016	2
Thereafter	6
Total minimum lease payments	16
Amounts representing interest	4
Present value of net minimum lease payments	$ 12

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The total of contractually required rental payments on leases meeting the criteria for capitalization.

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Amount necessary to reduce net minimum lease payments to present value calculated at the lesser of the interest rate implicit in the lease (if known) or the entity's incremental borrowing rate (as defined) at inception of the lease.

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The discounted value of future cash flows under leases meeting the criteria for capitalization.

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The total of future contractually required payments on leases defined as operating.

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