Operating Property (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 26, 2015
Property, Plant and Equipment [Line Items]
Land	$ 15,259	$ 9,148
Buildings and improvements	56,413	39,532
Trailing equipment	342,813	311,449
Other equipment	48,732	48,389
Total operating property, gross	463,217	408,518
Less accumulated depreciation and amortization	190,374	182,591
Total operating property, net	$ 272,843	$ 225,927