Income Taxes - Total Provision Allocated In Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Income (loss) from continuing operations	$ 4,893	$ (24,042)	$ (21,398)
Total provision (benefit)	277	(24,042)	(21,398)
Continuing operations [Member]
Operating Loss Carryforwards [Line Items]
Income (loss) from continuing operations	4,893	(24,042)	(21,398)
Discontinued operations
Operating Loss Carryforwards [Line Items]
Loss from discontinued operations	$ (4,616)	$ 0	$ 0