Goodwill and Intangible Assets - Additional Information (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Bank Servicing Fees	$ 196,000,000us-gaap_ServicingFeesNet	$ 87,000,000us-gaap_ServicingFeesNet	$ 260,000,000us-gaap_ServicingFeesNet
Goodwill, Transfers		0us-gaap_GoodwillTransfers
Consumer Banking and Private Wealth Management [Member]
Goodwill, Transfers		300,000,000
Wholesale Banking [Member]
Goodwill, Transfers		(300,000,000)
Mortgage Servicing Rights, Fair Value [Member]
Bank Servicing Fees	329,000,000	317,000,000	333,000,000
Qualitative and Quantitative Information, Transferor's Continuing Involvement, Principal Amount Outstanding	142,100,000,000	136,700,000,000
Principal Amount Outstanding of Loans Serviced For Third Parties	$ 115,500,000,000	$ 106,800,000,000

Principal Amount Outstanding of Loans Serviced for Third Parties

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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- Definition

Amount of transfers of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized among segments.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue from servicing real estate mortgages, credit cards, and other financial assets held by others. Includes premiums received in lieu of regular servicing fees.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13 (d))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Details

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- Details

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- Details

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