Goodwill and Intangible Assets Goodwill and Intangible Assets (Summary of CDI Carrying Value and Amortization) (Details) (Core deposit intangible, USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Core deposit intangible
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 34	$ 34
Accumulated amortization	(21)	(18)
Net carrying amount	$ 13	$ 16

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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