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Goodwill (Details)
12 Months Ended
Dec. 31, 2020
USD ($)
segment
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Goodwill [Line Items]      
Goodwill impairment $ 0 $ 0 $ 0
Number of reportable segments | segment 2    
AMS      
Goodwill [Line Items]      
Accumulated impairment losses $ 0    
EP      
Goodwill [Line Items]      
Accumulated impairment losses $ 2,700,000