Summary of Reclassifications Out of AOCI (Detail) - USD ($) $ in Thousands		3 Months Ended						4 Months Ended		12 Months Ended
		Dec. 31, 2016	Oct. 08, 2016	Jul. 16, 2016	Jan. 02, 2016	Oct. 10, 2015	Jul. 18, 2015	Apr. 23, 2016	Apr. 25, 2015	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes										$ 249,537	$ 293,031	$ 268,054
Tax benefit										(85,761)	(103,840)	(92,315)
Net income		$ 13,042	$ 40,216	$ 51,155	$ 32,246	$ 43,796	$ 51,760	$ 59,363	$ 61,389	163,776	189,191	175,739
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax	[1]									(11,800)	(7,952)	(13,369)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes										3,399	5,413	3,366
Gains/Losses on Cash Flow Hedges
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax										(3,399)	(5,413)
Gains/Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	[1]									(5,528)	(8,801)	(5,473)
Tax benefit	[1]									2,129	3,388	2,107
Net income	[1]									(3,399)	(5,413)	(3,366)
Pension and postretirement benefit items, prior service credits
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1],[2]									(175)	267	469
Pension and postretirement benefit items, Settlement losses
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1],[2]									(6,646)		(15,387)
Pension and postretirement benefit items, actuarial losses
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1],[2]									(6,840)	(4,395)	(1,348)
Accumulated Defined Benefit Plans Adjustment
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Tax benefit	[1]									5,260	1,589	6,263
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]									(13,661)	(4,128)	(16,266)
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax	[1]									(8,401)	(2,539)	(10,003)
Interest Rate Contracts | Gains/Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense	[1]									(221)	(250)	(255)
Commodity Contract | Gains/Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Cost of sales	[1],[3]									$ (5,307)	$ (8,551)	$ (5,218)

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

[2] These items are included in the computation of net periodic pension cost. See Note 19, Postretirement Plans, for additional information.

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