Common Stock - Additional Information 2 (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2018 |
Dec. 31, 2017 |
Jun. 30, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Unrecognized compensation expense related to stock options granted | $ 1,600,000 | $ 1,600,000 | $ 2,000,000 | |
| Common shares reserved for awards currently outstanding | 0 | |||
| Stock Options [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Weighted-average period, restricted stock awards | 3 years | |||
| Restricted Stock Unit [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Weighted-average period, restricted stock awards | 3 years | |||
| Award vesting period | 4 years | |||
| Stock based compensation expense | $ 37,000 | $ 37,000 | ||
| Common shares reserved for awards currently outstanding | 20,394 | 20,394 | 21,066 | |
| Total unrecognized compensation expense related to the Company's restricted stock unit awards | $ 500,000 | $ 500,000 |
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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 Unrecognized cost of unvested 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 The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. 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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