Information Regarding Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 28, 2020	Mar. 30, 2019	Dec. 28, 2019
Segment Reporting Information [Line Items]
External revenue	$ 927,566	$ 1,033,000
Internal revenue	9,079	9,614
Investment income	1,167	1,138
Operating income	54,005	80,896
Expenditures on long-lived assets	5,799	4,576
Goodwill	37,182	38,343	$ 38,508
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue	913,884	1,018,961
Operating income	55,044	67,583
Expenditures on long-lived assets	5,799	4,576
Goodwill	37,182	38,343
Insurance
Segment Reporting Information [Line Items]
External revenue	13,682	14,039
Internal revenue	9,079	9,614
Investment income	1,167	1,138
Operating income	$ (1,039)	$ 13,313

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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