Income Taxes - Schedule of Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current income tax expense:
Federal	$ (70)	$ (12)	$ (6)
State	48	23	45
Foreign	677	790	327
Total current income tax expense	655	801	366
Deferred income tax expense:
Federal	(483)	(16,141)	4,109
State	562	(248)	311
Foreign	(586)	(459)	(82)
Total deferred income tax expense	(507)	(16,848)	4,338
Total provision for (benefit from) income taxes	$ 148	$ (16,047)	$ 4,704