Income Tax - Reconciliation of Unrecognized Tax Benefits of Uncertain Tax Positions (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Income Tax Disclosure [Abstract] | |||
| Unrecognized tax benefits, Beginning Balance | $ 715 | $ 699 | $ 683 |
| Additions based on tax positions related to the current year | 0 | 16 | 16 |
| Additions based on tax positions related to prior years | 0 | 0 | 0 |
| Unrecognized tax benefits, Ending Balance | $ 715 | $ 715 | $ 699 |
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- References No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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