Goodwill and Identifiable Intangible Assets - Identifiable Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (in years)	18 years
Gross Carrying Amount	$ 632	$ 661
Accumulated Amortization	389	376
Net Carrying Amount	243	285
Customer Contractual Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (in years)	20 years
Gross Carrying Amount	440	466
Accumulated Amortization	262	253
Net Carrying Amount	178	213
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (in years)	11 years
Gross Carrying Amount	165	168
Accumulated Amortization	111	108
Net Carrying Amount	54	60
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (in years)	18 years
Gross Carrying Amount	27	27
Accumulated Amortization	16	15
Net Carrying Amount	$ 11	$ 12

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

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

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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

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

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

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