XML 1083 R65.htm IDEA: XBRL DOCUMENT v3.8.0.1
Segment Information - Additional Information (Detail)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 30, 2017
USD ($)
Sep. 30, 2017
USD ($)
Jul. 01, 2017
USD ($)
Apr. 01, 2017
USD ($)
Dec. 31, 2016
USD ($)
Sep. 24, 2016
USD ($)
Jun. 25, 2016
USD ($)
Mar. 26, 2016
USD ($)
Dec. 30, 2017
USD ($)
Customer
Segment
Dec. 31, 2016
USD ($)
Customer
Dec. 26, 2015
USD ($)
Customer
Sep. 20, 2017
Segment Reporting Information [Line Items]                        
External revenue | $ $ 1,051,592 $ 943,430 $ 870,434 $ 780,908 $ 892,829 $ 787,938 $ 775,223 $ 711,644 $ 3,646,364 $ 3,167,634 $ 3,321,091  
Number of segments | Segment                 2      
Number of customers accounting for 10 percent or more of total revenue | Customer                 0 0 0  
No single customer accounted for benchmark percentage to be considered major customer                 10.00% 10.00% 10.00%  
Fletes Avella | Landstar Metro                        
Segment Reporting Information [Line Items]                        
Ownership interest acquired by affiliates                       30.00%
Fletes Avella | Landstar Servicios                        
Segment Reporting Information [Line Items]                        
Ownership interest acquired by affiliates                       30.00%