Revenues (Disaggregation of Revenue by Geographic Region) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 54,550	$ 52,850
Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	39,430	37,232
Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	15,120	15,618
United States [Member]
Disaggregation of Revenue [Line Items]
Revenues	20,968	25,345
United States [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	17,440	19,564
United States [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	3,528	5,781
Canada [Member]
Disaggregation of Revenue [Line Items]
Revenues	29,366	24,996
Canada [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	20,807	16,621
Canada [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	8,559	8,375
Other Countries [Member]
Disaggregation of Revenue [Line Items]
Revenues	4,216	2,509
Other Countries [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,183	1,047
Other Countries [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 3,033	$ 1,462