Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 0	$ (18)	$ 111
State	(14)	(13)	0
Foreign	0	0	(65)
Total current	(14)	(31)	46
Deferred:
Federal	0	(2)	534
Foreign	0		0
Total deferred	0	(2)	534
Income tax benefit (expense)	$ (14)	$ (33)	$ 580