Debt (Schedule of Senior Notes) (Details) € in Millions, $ in Millions	9 Months Ended
Sep. 30, 2015 EUR (€)	Sep. 30, 2015 USD ($)
Senior Unsecured Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes \| €	€ 300
Interest rate	3.25%	3.25%
Date of maturity	Oct. 15, 2019
Senior Unsecured Notes Due 2022 [Member]
Debt Instrument [Line Items]
Senior notes		$ 500
Interest rate	4.625%	4.625%
Date of maturity	Nov. 15, 2022
Senior Unsecured Notes Due 2021 [Member]
Debt Instrument [Line Items]
Senior notes		$ 400
Interest rate	5.875%	5.875%
Date of maturity	Jun. 15, 2021

Face (par) amount of debt instrument at time of issuance.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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