XML 88 R75.htm IDEA: XBRL DOCUMENT v3.10.0.1
Detail of Certain Balance Sheet Accounts - Property and Equipment (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Property, Plant and Equipment [Line Items]    
Land $ 61,305 $ 48,832
Buildings and leasehold improvements 208,974 155,628
Operating equipment and vehicles 1,865,917 1,834,715
Office equipment, furniture and fixtures and information technology systems 212,769 170,115
Construction work in progress 19,507 60,587
Property and equipment, gross 2,368,472 2,269,877
Less — Accumulated depreciation and amortization (1,092,440) (981,275)
Property and equipment, net $ 1,276,032 $ 1,288,602
Minimum | Buildings and leasehold improvements    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 5 years  
Minimum | Operating equipment and vehicles    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 1 year  
Minimum | Office equipment, furniture and fixtures and information technology systems    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 3 years  
Maximum | Buildings and leasehold improvements    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 30 years  
Maximum | Operating equipment and vehicles    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 25 years  
Maximum | Office equipment, furniture and fixtures and information technology systems    
Property, Plant and Equipment [Line Items]    
Estimated useful lives 10 years