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Revenue Recognition - Change in Contract Liabilities (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Revenue from Contract with Customer [Abstract]    
Balance as of January 1 $ 268.3 $ 247.4
Revenue recognized (15.2) (13.3)
Revenue deferred 17.9 20.1
Balance as of March 31 $ 271.0 $ 254.2