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Segment Information Narrative (Details)
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Revenue, Major Customer [Line Items]    
Number of reportable segments 3  
Concentration risk, supplier We currently buy a majority of our integrated circuit board assemblies from three suppliers. Management believes that other suppliers could provide similar products, but a change in suppliers, disputes with our suppliers, or unexpected constraints on the suppliers' production capacity could adversely affect operating results.  
Sales [Member] | Customer A [Member]    
Revenue, Major Customer [Line Items]    
Concentration Risk, Percentage 11.00% 11.00%