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Revenue - Narratives (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Revenue from Contract with Customer [Abstract]        
Contract revenue recognized $ 24.3 $ 25.8 $ 76.2 $ 91.3
Remaining performance obligation $ 684.9   $ 684.9  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01        
Disaggregation of Revenue        
Revenue, remaining performance obligation 83.70%   83.70%  
Performance obligations expected to be satisfied, expected timing 12 months   12 months