Common Stock - Restricted Stock Unit Awards - Additional Information (Detail) - Restricted Stock Unit [Member] - USD ($) |
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 [Line Items] | |||
| Award vesting period | 4 years | ||
| Stock based compensation expense | $ 200,000 | $ 100,000 | $ 0 |
| Total unrecognized compensation expense related to the Company's restricted stock unit awards | $ 400,000 | ||
| Weighted-average period, restricted stock awards | 2 years 6 months 29 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 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 Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation. 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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- Details
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