Loss Reclassified From AOCI for Commodity Contracts (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 15, 2017	Jul. 16, 2016	Jul. 15, 2017	Jul. 16, 2016
Accumulated Other Comprehensive Income Loss [Line Items]
Net of tax		$ 320	$ 803	$ 794	$ 1,946
Gains/Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Gross loss reclassified from AOCI into income	[1]	520	1,305	1,291	3,165
Tax benefit	[1]	(200)	(502)	(497)	(1,219)
Net of tax	[1]	320	803	794	1,946
Commodity Contract | Gains/Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Gross loss reclassified from AOCI into income	[1],[2]	$ 487	$ 1,248	1,214	3,030
Tax benefit				(467)	(1,167)
Net of tax				$ 747	$ 1,863

[1] Amounts in parentheses indicate debits to determine net income.

[2] Amounts are presented as an adjustment to reconcile net income to net cash provided by operating activities on the Condensed Consolidated Statements of Cash Flows.