Stock Plans (Details 3) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
| Total stock-based compensation expenses | $ 1,557 | $ 1,687 | $ 1,039 |
| Increase in basic net income (loss) per share (in dollars per share) | $ (0.27) | $ (0.08) | $ (0.05) |
| Increase in diluted net income (loss) per share (in dollars per share) | $ (0.27) | $ (0.08) | $ (0.05) |
| Research and development [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
| Total stock-based compensation expenses | $ 575 | $ 519 | $ 386 |
| General and administrative [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
| Total stock-based compensation expenses | $ 982 | $ 1,168 | $ 653 |
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- Definition Share based compensation expense impact on basic earnings per share No definition available.
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- Definition Share based compensation expense impact on diluted earnings per share. No definition available.
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. 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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