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Revenue from Contracts with Customers - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Revenue from Contract with Customer [Abstract]          
Contract with customer, liability $ 35.9   $ 35.9   $ 69.9
Contract with customer, revenue recognized $ 45.8 $ 47.9 $ 48.5 $ 50.1