Fair Value Measurements and Derivatives - Additional Information (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	$ 334invest_DerivativeNotionalAmount
Net investment hedge translation adjustment	2
Cash flow hedge loss to be reclassified to earnings during next 12 months	(11)	(10)
Foreign Exchange Forward [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	324	296
Currency Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	10	10
United States of America, Dollars [Member] \| Foreign Exchange Forward [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	176
Net Investment Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	98
Net Investment Hedging [Member] \| Foreign Exchange Forward [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	98
Net Investment Hedging [Member] \| United States of America, Dollars [Member] \| Foreign Exchange Forward [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amounts of derivatives	$ 98

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

Cumulative adjustment resulting from gains and losses on foreign currency derivatives that are designated as, and are effective as, hedges of a net investment in a foreign entity, commencing as of the designation date. Adjustment reported in equity as part of accumulated other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 30

-Section 45

-Paragraph 20

-Subparagraph (b),(c)

-URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32211-110900

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