Information Regarding Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018	Dec. 29, 2018
Segment Reporting Information [Line Items]
External revenue	$ 1,033,000	$ 1,047,926
Internal revenue	9,614	7,498
Investment income	1,138	861
Operating income	80,896	75,153
Expenditures on long-lived assets	4,576	3,814
Goodwill	38,343	39,363	$ 38,232
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue	1,018,961	1,035,640
Operating income	67,583	67,300
Expenditures on long-lived assets	4,576	3,814
Goodwill	38,343	39,363
Insurance
Segment Reporting Information [Line Items]
External revenue	14,039	12,286
Internal revenue	9,614	7,498
Investment income	1,138	861
Operating income	$ 13,313	$ 7,853

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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