Income Taxes - Change in Valuation Allowance (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Deferred Tax Assets, Valuation Allowance [Roll Forward] | |||
| Valuation allowance, beginning balance | $ 43,269 | $ 53,199 | $ 73,659 |
| Acquired valuation allowance from business combination | (1,400) | ||
| Increase (decrease) in valuation allowance | 42,124 | (9,930) | (19,060) |
| Valuation allowance, ending balance | $ 85,393 | $ 43,269 | $ 53,199 |
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- Definition Deferred Tax Assets, Valuation Allowance [Roll Forward] No definition available.
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- Definition Deferred Taxes, Business Combinations, Valuation Allowance No definition available.
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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