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Asset Retirement Obligations (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Beginning Balance $ 12.3 $ 11.4
Liabilities settled 0.0 (0.1)
Accretion expense 0.9 0.9
Revisions in estimated cash flows 0.6 0.1
Ending Balance 13.8 12.3
Current portion of asset retirement obligation liabilities $ 0.4 $ 0.7