Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
U.S. federal	$ 261	$ 0	$ (624)
State	(38)	(254)	226
Foreign	(245)	(241)	(308)
Total Current	(22)	(495)	(706)
Deferred
U.S. federal	13,028	5,403	3,702
State	0	(280)	107
Foreign	(21,659)	(6,079)	2,360
Total Deferred	(8,631)	(956)	6,169
Changes in valuation allowance	(13,028)	(3,613)	(4,604)
Income tax (expense) benefit	$ (21,681)	$ (5,064)	$ 859