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Revenue - Additional Information (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Revenue from Contract with Customer [Abstract]      
Revenue, performance obligation satisfied over time, percentage (less than) 3.00% 3.00%  
Contract assets $ 2.1 $ 4.6 $ 3.6
Contract liabilities $ 1.1 $ 0.9 $ 0.2