Premises and Equipment Leases (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leased Assets [Line Items]
Amortization Of Deferred Gain On Sale Lease Back Of Premises	$ 53	$ 58	$ 67
Operating Leases, Future Minimum Payments Due, Next Twelve Months	205
Capital Leases, Future Minimum Payments Due, Next Twelve Months	2
Operating Leases, Future Minimum Payments, Due in Two Years	201
Capital Leases, Future Minimum Payments Due in Two Years	2
Operating Leases, Future Minimum Payments, Due in Three Years	183
Capital Leases, Future Minimum Payments Due in Three Years	2
Operating Leases, Future Minimum Payments, Due in Four Years	107
Capital Leases, Future Minimum Payments Due in Four Years	2
Operating Leases, Future Minimum Payments, Due in Five Years	87
Capital Leases, Future Minimum Payments Due in Five Years	3
Operating Leases, Future Minimum Payments, Due Thereafter	328
Capital Leases, Future Minimum Payments Due Thereafter	0
Operating Leases, Future Minimum Payments Due	1,111
Capital Leases, Future Minimum Payments Due	11
Capital Leases, Future Minimum Payments, Interest Included in Payments	2
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments	9
Sale Leaseback Transaction, Deferred Gain, Gross	$ 162	$ 215

Amortization of deferred gain on sale lease back of premises.

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Amount of minimum lease payments for capital leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 40

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