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Revenue - Narrative (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Revenue From Contract With Customer [Abstract]          
Performance obligation unsatisfied or partially satisfied $ 117,500,000   $ 117,500,000    
Impairment charges 0 $ 0 0 $ 0  
Contract cost, accumulated amortization 5,000,000.0   5,000,000.0   $ 4,300,000
Contract cost, accumulated impairment $ 0 $ 0 $ 0 $ 0