Stock Plans - Schedule of Restricted Stock Unit Activity (Detail) - Restricted Stock Units [Member] |
3 Months Ended |
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Mar. 31, 2019
$ / shares
shares
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Shares, Unvested, Beginning Balance | shares | 49,143 |
| Shares, Granted | shares | 50,535 |
| Shares, Unvested, Ending Balance | shares | 99,678 |
| Weighted Average Grant Date Fair Value, Unvested, Beginning Balance | $ / shares | $ 12.57 |
| Weighted Average Grant Date Fair Value, Granted | $ / shares | 5.65 |
| Weighted Average Grant Date Fair Value, Unvested, Ending Balance | $ / shares | $ 9.06 |
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). 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 The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. 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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