Information Regarding Reportable Business Segments (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013	Dec. 28, 2013
Segment Reporting Information [Line Items]
External revenue from continuing operations	$ 819,320,000	$ 675,535,000	$ 2,321,960,000	$ 1,972,805,000
Investment income	332,000	366,000	1,027,000	1,111,000
Internal revenue	5,791,000	5,999,000	22,373,000	22,808,000
Operating income from continuing operations	59,577,000	46,614,000	163,163,000	136,849,000
Expenditures on long-lived assets from continuing operations	7,777,000	2,056,000	9,131,000	4,800,000
Goodwill	31,134,000	57,470,000	31,134,000	57,470,000	31,134,000
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue from continuing operations	809,309,000	666,404,000	2,292,982,000	1,945,572,000
Operating income from continuing operations	51,626,000	41,040,000	143,828,000	116,861,000
Expenditures on long-lived assets from continuing operations	7,777,000	2,056,000	9,131,000	4,800,000
Goodwill	31,134,000	57,470,000	31,134,000	57,470,000
Insurance
Segment Reporting Information [Line Items]
External revenue from continuing operations	10,011,000	9,131,000	28,978,000	27,233,000
Investment income	332,000	366,000	1,027,000	1,111,000
Internal revenue	5,791,000	5,999,000	22,373,000	22,808,000
Operating income from continuing operations	$ 7,951,000	$ 5,574,000	$ 19,335,000	$ 19,988,000