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FINANCIAL STATEMENT PRESENTATION - Other Operating Property and Equipment (Details)
6 Months Ended
Jun. 30, 2021
Buildings  
Other operating property and equipment  
Estimated useful lives 20 years
Automobiles  
Other operating property and equipment  
Estimated useful lives 3 years
Computers  
Other operating property and equipment  
Estimated useful lives 3 years
Computer software  
Other operating property and equipment  
Estimated useful lives 5 years
Fixtures, furniture and equipment  
Other operating property and equipment  
Estimated useful lives 5 years
Trailers  
Other operating property and equipment  
Estimated useful lives 7 years
Heavy equipment | Minimum  
Other operating property and equipment  
Estimated useful lives 8 years
Heavy equipment | Maximum  
Other operating property and equipment  
Estimated useful lives 10 years