Operating Property (Detail) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Property, Plant and Equipment [Line Items]
Land	$ 9,148	$ 9,148
Buildings and improvements	39,532	38,790
Trailing equipment	311,449	267,685
Other equipment	48,389	47,261
Total operating property, gross	408,518	362,884
Less accumulated depreciation and amortization	182,591	160,681
Total operating property, net	$ 225,927	$ 202,203