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Asset Retirement Obligation - Schedule of Change in Asset Retirement Obligation (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]      
Beginning of period $ 34.2 $ 34.7  
Accretion expense 2.5 2.4 $ 2.3
Additions 0.3 0.2  
Liabilities settled (2.1) (2.7)  
Foreign currency translation adjustments 0.2 (0.4)  
End of period $ 35.1 $ 34.2 $ 34.7