Operating Property (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Land	$ 15,834	$ 15,259
Buildings and improvements	58,484	58,018
Trailing equipment	425,595	398,404
Other equipment	66,791	62,504
Total operating property, gross	566,704	534,185
Less accumulated depreciation and amortization	280,849	250,153
Total operating property, net	$ 285,855	$ 284,032