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Commitments and Contingencies (Details)
$ in Millions
Jul. 29, 2022
USD ($)
Jun. 30, 2022
USD ($)
Dec. 31, 2021
USD ($)
Oct. 09, 2015
buyer
Dec. 31, 2007
USD ($)
Forecast          
Long-term Purchase Commitment [Line Items]          
Securities class action settlement $ 4.6        
Patriot          
Long-term Purchase Commitment [Line Items]          
Number of buyers | buyer       2  
Black Lung Occupational Disease Liability | Patriot | Spinoff          
Long-term Purchase Commitment [Line Items]          
Initially determined potential exposure from patriot bankruptcy   $ 86.6 $ 87.2   $ 150.0
Capital Addition Purchase Commitments          
Long-term Purchase Commitment [Line Items]          
Unrecorded unconditional purchase obligation (within next five years)   42.3      
Unrecorded unconditional purchase obligation (within next 12 months)   $ 35.4