Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)	Sep. 30, 2018 $ / shares shares	Sep. 30, 2018 € / shares shares	Dec. 31, 2017 $ / shares shares	Dec. 31, 2017 € / shares shares
Preference shares, nominal value (USD per share) \| $ / shares	$ 0.000115		$ 0.000115
Preference shares, shares authorized	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000
Preference shares, shares issued	0	0	0	0
Ordinary shares, $0.000304635 nominal value [Member]
Ordinary shares, nominal value (euro per share) \| $ / shares	$ 0.000304635		$ 0.000304635
Ordinary shares, shares authorized	1,510,003,775	1,510,003,775	1,510,003,775	1,510,003,775
Ordinary shares, shares issued	129,912,918	129,912,918	132,139,581	132,139,581
Ordinary shares, shares outstanding	129,912,918	129,912,918	132,139,581	132,139,581
Treasury shares	17,519	17,519	17,519	17,519
Ordinary shares, €1 nominal value [Member]
Ordinary shares, nominal value (euro per share) \| € / shares		€ 1		€ 1
Ordinary shares, shares authorized	40,000	40,000	40,000	40,000
Ordinary shares, shares issued	40,000	40,000	40,000	40,000
Treasury shares	40,000	40,000	40,000	40,000

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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-Section S99
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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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