Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Deferred tax benefit related to discontinued operations	$ 100	$ 400
Tax expense associated with deferred tax asset valuation allowance	25
Tax Act, adjustment to value of deferred tax asset	4,500
Tax Act, tax on accumulated earnings of foreign subsidiaries	$ 400
Percentage for recognition of uncertain tax positions, minimum	50.00%
Effective income tax rate	1032.80%	31.40%
Increase in effective tax rate for decrease in federal tax rate	1241.00%	0.00%
Increase in effective tax rate for repatriation tax on accumulated foreign earnings, percent	110.50%	0.00%
Federal
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	$ 5,700
Operating loss carryforwards	5,000
State
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	300
Operating loss carryforwards	$ 1,500