Gain or Loss Reclassified from Accumulated Other Comprehensive Income for Commodity Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 18, 2015	Jul. 12, 2014	Jul. 18, 2015	Jul. 12, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax	$ 1,251	$ 442	$ 2,838	$ 3,514
Commodity Contract
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gross loss reclassified from AOCI into income			4,481	5,578
Tax benefit			(1,725)	(2,146)
Net of tax			$ 2,756	$ 3,432