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Property and Equipment - Additional Information (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2011
Property, Plant and Equipment [Line Items]        
Property and Equipment, gross $ 546,010 $ 479,013    
Equipment, capital lease obligation       $ 26,400
Equipment, capital lease obligation, net 14,700 17,400    
Depreciation and amortization expense related to property and equipment 35,900 28,300 $ 20,200  
Amortization expense under capital lease obligation 2,600 2,600 $ 2,600  
Transportation Equipment [Member]        
Property, Plant and Equipment [Line Items]        
Property and Equipment, gross $ 405,322 $ 346,055