Revenues (Disaggregation of Revenue by Geographic Region) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 8,732	$ 39,768	$ 63,282	$ 92,618
Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	4,858	29,945	44,288	67,177
Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	3,874	9,823	18,994	25,441
United States [Member]
Disaggregation of Revenue [Line Items]
Revenues	4,604	26,743	25,572	52,088
United States [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	3,687	21,069	21,127	40,633
United States [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	917	5,674	4,445	11,455
Canada [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,500	11,506	30,866	36,502
Canada [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,171	8,801	21,978	25,422
Canada [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	329	2,705	8,888	11,080
Other Countries [Member]
Disaggregation of Revenue [Line Items]
Revenues	2,628	1,519	6,844	4,028
Other Countries [Member] | Product sales [Member]
Disaggregation of Revenue [Line Items]
Revenues		75	1,183	1,122
Other Countries [Member] | Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 2,628	$ 1,444	$ 5,661	$ 2,906