Income Taxes - Schedule of (Provision for) Benefit from Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current income taxes:
Federal	$ (416)	$ (1,533)	$ (649)
State	(131)	(42)	11
Foreign		6	17
Total current income taxes	(547)	(1,569)	(621)
Deferred income taxes:
Federal	(6)	(477)	30
State		297	105
Foreign			2
Total deferred income taxes	(6)	(180)	137
Total income tax provision	$ (553)	$ (1,749)	$ (484)