Equity (Narrative) (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Number of options exercised | 17,402 | 35,769 |
| Increase in equity | $ 0.3 | $ 0.5 |
| Stock option term | 10 years | |
| Vesting period | 4 years | |
| Unrecognized compensation cost | $ 18.8 | |
| Weighted average period for recognition | 2 years 7 months 6 days | |
| Restricted Stock Units (RSUs) [Member] | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Unrecognized compensation cost | $ 5.2 | |
| Weighted average period for recognition | 2 years 7 months 6 days | |
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- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The increase (decrease) in stockholders' equity during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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