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Segment Information - Narrative (Details) - segment
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Product Information [Line Items]      
Number of reportable segments 3    
Revenue | Energy Equipment Group | Customer Concentration Risk      
Product Information [Line Items]      
Revenue concentration risk, percentage 18.20% 19.40% 22.90%