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Summary of Significant Accounting Principles (Tables)
6 Months Ended
Jun. 30, 2021
Accounting Policies [Abstract]  
Schedule of depreciable lives of property, plant and equipment

Automobiles and trucks

    

3 to 5 years

Buildings and improvements

 

5 to 30 years

Construction equipment

 

3 to 15 years

Vessels and other equipment

 

1 to 15 years

Office equipment

 

1 to 5 years