Income Taxes - Income tax provision (Details) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018  | 
Dec. 31, 2017  | 
Dec. 31, 2016  | 
|
| Income Tax Disclosure [Abstract] | |||
| Current, Federal | $ (1,888) | $ (1,055) | $ 1,304 | 
| Current, State | 1,176 | 671 | 303 | 
| Current, Foreign | 30 | 161 | (106) | 
| Current, Total | (682) | (223) | 1,501 | 
| Deferred, Federal | 2,662 | (6,683) | 2,341 | 
| Deferred, State | 2,530 | 1,853 | 106 | 
| Deferred, Foreign | 303 | 262 | 422 | 
| Deferred, Total | 5,495 | (4,568) | 2,869 | 
| Income tax (benefit) provision | $ 4,813 | $ (4,791) | $ 4,370 | 
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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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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/disclosureRef 
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