Significant Changes Due To Topic 606 (Summary of the Effects of Adoption of ASC Topic 606 on the Company's unaudited Consolidated Statement of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net income (loss)	$ 757	$ (655)
Inventories	$ (1,183)	(553)
Accounting Standards Update 2014-09 [Member]
Net income (loss)		(655)
Inventories		(553)
Other current assets		(631)
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Net income (loss)		158
Inventories		352
Other current assets		(510)
Accounting Standards Update 2014-09 [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Net income (loss)		(813)
Inventories		(905)
Other current assets		$ (121)