Income Taxes - Components of Benefit From Income Taxes (Details) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017  | 
Dec. 31, 2016  | 
Dec. 31, 2015  | 
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| Current: | |||
| Federal | $ 20,277 | $ 7,151 | $ 12 | 
| State | 2 | (81) | 100 | 
| Foreign | 1,216 | 1,648 | 456 | 
| Total current taxes | 21,495 | 8,718 | 568 | 
| Deferred foreign taxes | (1,647) | 273 | (16) | 
| Income tax provision | $ 19,848 | $ 8,991 | $ 552 | 
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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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