Income Taxes, Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Effective income tax rate reconciliation [Abstract]
Statutory federal income tax benefit	$ 4,548	$ 5,388
State tax benefit, net of federal taxes	48	2
Foreign tax	0	3
R&D tax credit	0	80
Foreign deferred exchange rate adjustments	899	0
Nondeductible/nontaxable items	(114)	(86)
New federal rate adjustment	(16,081)	0
Other	(1,085)	(257)
Valuation allowance decrease (increase)	11,779	(5,076)
Total income tax benefit (expense)	$ (6)	$ 54