Income Taxes - Schedule of Unrecognized Tax Benefit Roll-Forward (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| As of the beginning of the year | $ 208 | $ 193 | $ 191 |
| Increases for tax positions of current years | 0 | 15 | 2 |
| Reductions for tax positions of prior years | (4) | 0 | 0 |
| As of the end of the year | $ 204 | $ 208 | $ 193 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. 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 decrease 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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- 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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