Income Taxes (Details 3) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Balance | $ 335 | $ 199 | $ 143 | $ 93 |
| Increase (decrease) of unrecognized tax benefits taken in prior years | 33 | 4 | (19) | 4 |
| Increase of unrecognized tax benefits related to current year | 119 | 132 | 75 | 46 |
| Balance | $ 487 | $ 335 | $ 199 | $ 143 |
| X | ||||||||||
- Definition Amount of increase (decrease) in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. No definition available.
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| X | ||||||||||
- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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