Stock Plans (Details Textual) - USD ($) shares in Thousands |
3 Months Ended | |
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Mar. 31, 2018 |
Mar. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Weighted-average period for recognizing non-vested stock option | 10 months 24 days | |
| Employee Stock Option [Member] | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total | $ 892,000 | |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 945 | 436 |
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- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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 Gross number of share options (or share units) granted during the period. No definition available.
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- Details
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