Information Regarding Reportable Business Segments (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
External revenue									$ 4,084,577,000	$ 4,615,144,000	$ 3,646,364,000
Internal revenue									46,587,000	37,872,000	37,110,000
Investment income									5,041,000	3,816,000	2,498,000
Interest and debt expense									3,141,000	3,354,000	3,166,000
Depreciation and amortization									44,468,000	43,570,000	40,560,000
Operating income	$ 66,519,000	$ 70,638,000	$ 80,851,000	$ 80,896,000	$ 86,088,000	$ 87,068,000	$ 83,426,000	$ 75,153,000	298,904,000	331,735,000	243,968,000
Expenditures on long-lived assets									19,416,000	9,747,000	15,586,000
Goodwill	38,508,000				38,232,000				38,508,000	38,232,000	39,065,000
Finance lease additions									29,054,000	46,595,000	33,560,000
Total assets	1,427,711,000				1,380,564,000				1,427,711,000	1,380,564,000	1,352,460,000
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue									4,028,336,000	4,562,796,000	3,599,382,000
Interest and debt expense									3,141,000	3,354,000	3,166,000
Depreciation and amortization									44,468,000	43,570,000	40,560,000
Operating income									258,742,000	303,426,000	209,615,000
Expenditures on long-lived assets									19,416,000	9,747,000	15,586,000
Goodwill	38,508,000				38,232,000				38,508,000	38,232,000	39,065,000
Finance lease additions									29,054,000	46,595,000	33,560,000
Total assets	1,168,944,000				1,175,040,000				1,168,944,000	1,175,040,000	1,132,766,000
Insurance
Segment Reporting Information [Line Items]
External revenue									56,241,000	52,348,000	46,982,000
Internal revenue									46,587,000	37,872,000	37,110,000
Investment income									5,041,000	3,816,000	2,498,000
Operating income									40,162,000	28,309,000	34,353,000
Total assets	$ 258,767,000				$ 205,524,000				$ 258,767,000	$ 205,524,000	$ 219,694,000