Common Shares (Details) € / shares in Units, € in Millions, $ in Millions	12 Months Ended
Dec. 31, 2016 EUR (€) € / shares shares	Dec. 31, 2015 € / shares shares	Dec. 31, 2016 USD ($)
Equity [Abstract]
Common shares, par value (in Euro per share) \| € / shares	€ 0.025	€ 0.025
Common shares outstanding, value	€ 1.6		$ 2.1
Common Stock, Shares Outstanding [Roll Forward]
Beginning balance (in shares)	62,470,881	60,902,695
Issuance of shares under share option and free share plans (in shares)	1,507,323	1,568,186
Ending balance (in shares)	63,978,204	62,470,881

Common Stock, Shares Outstanding [Roll Forward]

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- Definition

Face amount or stated value per share of common stock.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.

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- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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