Share-based Compensation - Unrecognized Share-Based Compensation Expense (Detail) $ in Thousands |
12 Months Ended |
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Dec. 31, 2017
USD ($)
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unrecognized Expense | $ 4,659 |
| Average Expected Recognition Period | 1 year 8 months 15 days |
| Stock option awards [Member] | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unrecognized Expense | $ 11 |
| Average Expected Recognition Period | 5 months 2 days |
| Restricted stock awards [Member] | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unrecognized Expense | $ 4,648 |
| Average Expected Recognition Period | 1 year 8 months |
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- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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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