Share-based Compensation - Summary of Stock Options and Changes (Management Equity Stock Option Plan) (Detail) - Management Equity Stock Option Plan [Member] |
12 Months Ended |
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Dec. 31, 2018
€ / shares
shares
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Stock options, Outstanding at January 1, 2018 | shares | 231,924 |
| Stock options, Granted | shares | 0 |
| Stock options, Exercised | shares | 231,924 |
| Stock options, Forfeited | shares | 0 |
| Stock options, Expired | shares | 0 |
| Stock options, Outstanding at December 31, 2018 | shares | 0 |
| Weighted average exercise price, Outstanding at January 1, 2018 | € / shares | € 35.72 |
| Weighted average exercise price, Granted | € / shares | 0 |
| Weighted average exercise price, Exercised | € / shares | 35.72 |
| Weighted average exercise price, Forfeited | € / shares | 0 |
| Weighted average exercise price, Expired | € / shares | 0 |
| Weighted average exercise price, Outstanding at December 31, 2018 | € / shares | € 0 |
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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. No definition available.
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- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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