Operating Property (Detail) - USD ($) $ in Thousands	Dec. 25, 2021	Dec. 26, 2020
Property, Plant and Equipment [Line Items]
Land	$ 16,328	$ 16,328
Buildings and improvements	65,034	64,314
Trailing equipment	479,300	433,400
Information technology hardware and software	91,115	72,560
Other equipment	9,708	9,801
Total operating property, gross	661,485	596,403
Less accumulated depreciation and amortization	344,099	299,407
Total operating property, net	$ 317,386	$ 296,996