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Postretirement Benefit Plans (Details)
 6 Months Ended 12 Months Ended
Nov. 30, 2020
USD ($)
Dec. 31, 2021
USD ($)
employees
Dec. 31, 2020
USD ($)
employees
May 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
employees
May 31, 2019
USD ($)
Multiemployer Defined Contributory Trust Plan [Member]            
Multiemployer Plans [Line Items]            
Number of employees in plan | employees   760 735   1,215  
Required defined contributory trust contribution, percent of earnings.   4.50% 4.50%   4.50%  
Required employer's contribution per hour per active employee     $ 0.90   $ 0.90  
Period Contributions   $ 1,900,000 2,400,000   $ 2,600,000  
Multiemployer Health and Welfare Plan [Member]            
Multiemployer Plans [Line Items]            
Number of employees in plan | employees         475  
Required employer's contribution per hour per active employee $ 7.00     $ 6.70   $ 6.40
Period Contributions     $ 5,800,000   $ 6,700,000