Summary of Significant Accounting Policies - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | |
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Mar. 31, 2019 |
Mar. 31, 2018 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Stock-based compensation expense | $ 385 | $ 355 |
| Stock Options | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Non-vested stock options unrecognized compensation expense | $ 4,034 | |
| Non-vested stock options unrecognized compensation expense, weighted-average period of recognition | 2 years 3 months 12 days | |
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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 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 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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- Details
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