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Summary of Significant Accounting Principles - Depreciable Lives of Property and Equipment (Details)
3 Months Ended
Mar. 31, 2017
Equipment improvement | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 3 years
Equipment improvement | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 7 years
Automobiles and trucks | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 3 years
Automobiles and trucks | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 5 years
Building and improvements | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 5 years
Building and improvements | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 30 years
Construction equipment | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 3 years
Construction equipment | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 15 years
Vessels and other equipment | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 1 year
Vessels and other equipment | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 15 years
Office equipment | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 1 year
Office equipment | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 5 years
Dry-docking capitalized costs | Minimum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 3 years
Dry-docking capitalized costs | Maximum  
Property, Plant and Equipment [Line Items]  
Property and equipment useful life 15 years