Income Taxes - Summary of Reconciliation of Unrecognized Tax Benefits (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 liability for unrecognized tax benefits | |||
| Balance at beginning of period | $ 934 | $ 773 | $ 577 |
| Additions based on tax positions related to current year | 128 | 161 | 176 |
| Additions for tax positions of prior years | 20 | ||
| Balance at end of period | $ 1,062 | $ 934 | $ 773 |
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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 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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