Segment Information (Sales By Geographic Location) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Total revenue	$ 2,792	$ 2,824
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	2,792	2,824
United States [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	2,151	2,234
Canada [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	624	565
Other Countries | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 17	$ 25