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Asset Retirement Obligation (Details)
$ in Millions
3 Months Ended 6 Months Ended
Mar. 31, 2022
USD ($)
Mar. 31, 2021
USD ($)
Jun. 30, 2021
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
ARO Loss Contingencies [Line Items]            
Asset Retirement Obligation, Liabilities Incurred $ 4.6   $ 20.2      
Number Of Consent Decrees 2          
Asset Retirement Obligation $ 1,771.4     $ 1,749.3 $ 1,393.9  
Surety Bonds Outstanding Delivered To EPA       249.7    
Asset retirement obligations $ 1,553.4     1,526.9    
Number Of Decades Remaining For Trust 3          
Asset Retirement Obligation, Liabilities Settled $ (54.1)   (163.1)      
Accretion expense for asset retirement obligations 19.6 $ 17.1 71.9      
Asset Retirement Obligation, Revision of Estimate 12.1   443.3      
Asset Retirement Obligation, Foreign Currency Translation Gain (Loss) 39.9   $ (16.9)      
Asset retirement obligations 218.0     222.4    
Unfavorable Regulatory Action | 2015 Consent Decrees With EPA            
ARO Loss Contingencies [Line Items]            
Asset retirement obligations, undiscounted       1,800.0    
Asset Retirement Obligation 20.0     603.0    
Bonnie Facility Trust [Member]            
ARO Loss Contingencies [Line Items]            
Assets Held-in-trust, Current           $ 21.0
Plant City and Bonnie Facilities            
ARO Loss Contingencies [Line Items]            
Asset retirement obligations $ 249.7     $ 262.9