Income Taxes - Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal	$ (11)	$ (10,608)	$ (2,001)
State	(19)	(940)	(216)
Foreign	0	7	8
Current, total	(30)	(11,541)	(2,209)
Deferred:
Federal	12	(5,256)	(93)
State	19	19	(11)
Foreign	0	0	0
Deferred, total	31	(5,237)	(104)
Total income tax provision (benefit)	$ 1	$ (16,778)	$ (2,313)