Information Regarding Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Dec. 29, 2018
Segment Reporting Information [Line Items]
External revenue	$ 1,045,040	$ 1,182,786	$ 2,078,040	$ 2,230,712
Internal revenue	17,753	15,419	27,367	22,917
Investment income	1,283	891	2,421	1,752
Operating income	80,851	83,426	161,747	158,579
Expenditures on long-lived assets	4,648	307	9,224	4,121
Goodwill	38,407	38,704	38,407	38,704	$ 38,232
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue	1,030,816	1,169,921	2,049,777	2,205,561
Operating income	68,336	78,998	135,919	146,298
Expenditures on long-lived assets	4,648	307	9,224	4,121
Goodwill	38,407	38,704	38,407	38,704
Insurance
Segment Reporting Information [Line Items]
External revenue	14,224	12,865	28,263	25,151
Internal revenue	17,753	15,419	27,367	22,917
Investment income	1,283	891	2,421	1,752
Operating income	$ 12,515	$ 4,428	$ 25,828	$ 12,281

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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