Information Regarding Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 29, 2018
Segment Reporting Information [Line Items]
External revenue	$ 1,011,658	$ 1,202,081	$ 3,089,698	$ 3,432,793
Internal revenue	9,611	7,496	36,978	30,413
Investment income	1,315	1,002	3,736	2,754
Operating income	70,638	87,068	232,385	245,647
Expenditures on long-lived assets	5,975	3,204	15,199	7,325
Goodwill	38,232	38,560	38,232	38,560	$ 38,232
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue	997,552	1,188,737	3,047,329	3,394,298
Operating income	64,848	80,878	200,767	227,176
Expenditures on long-lived assets	5,975	3,204	15,199	7,325
Goodwill	38,232	38,560	38,232	38,560
Insurance
Segment Reporting Information [Line Items]
External revenue	14,106	13,344	42,369	38,495
Internal revenue	9,611	7,496	36,978	30,413
Investment income	1,315	1,002	3,736	2,754
Operating income	$ 5,790	$ 6,190	$ 31,618	$ 18,471

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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