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Significant Accounting Policies - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 26, 2015
Dec. 27, 2014
Dec. 28, 2013
Significant Accounting Policies [Line Items]      
Stock options excluded from calculation of diluted earnings per share, antidilutive 0 0 143,000
Dividends payable per share   $ 1.00  
Dividend payable date   Jan. 26, 2015  
Dividend record date   Jan. 12, 2015  
Dividends payable   $ 44,794,000  
Dividend declared date   Dec. 04, 2014  
Buildings And Improvements      
Significant Accounting Policies [Line Items]      
Depreciated life 30 years    
Trailing Equipment | Minimum      
Significant Accounting Policies [Line Items]      
Depreciated life 7 years    
Trailing Equipment | Maximum      
Significant Accounting Policies [Line Items]      
Depreciated life 10 years    
Hardware And Software | Minimum      
Significant Accounting Policies [Line Items]      
Depreciated life 3 years    
Hardware And Software | Maximum      
Significant Accounting Policies [Line Items]      
Depreciated life 7 years    
Commercial Trucking Claims      
Significant Accounting Policies [Line Items]      
Company retained liability per claim $ 5,000,000    
General Liability Claim      
Significant Accounting Policies [Line Items]      
Company retained liability per claim 1,000,000    
Workers' Compensation Claim      
Significant Accounting Policies [Line Items]      
Company retained liability per claim 250,000    
Cargo Claim      
Significant Accounting Policies [Line Items]      
Company retained liability per claim $ 250,000