Effect of Derivative Instruments for Deferred Gains And (Losses) on Closed Contracts and Effective Portion in Fair Value on AOCI, Utilized for Risk Management Purposes (Detail) - USD ($) $ in Thousands		3 Months Ended												4 Months Ended				12 Months Ended
		Dec. 30, 2017	[1]	Oct. 07, 2017	[1],[2]	Jul. 15, 2017	[1],[2]	Dec. 31, 2016	[1]	Oct. 08, 2016	[1],[2]	Jul. 16, 2016	[1],[2]	Apr. 22, 2017	[1],[2]	Apr. 23, 2016	[1],[2]	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of derivatives																		$ (6,789)	$ 5,730	$ (4,195)
Production costs		$ 456,800		$ 476,170		$ 468,152		$ 450,462		$ 476,760		$ 477,955		$ 607,941		$ 621,190		2,009,063	2,026,367	1,963,153
Income before income taxes																		149,293	249,537	293,031
Reclassification out of Accumulated Other Comprehensive Income
Derivative Instruments, Gain (Loss) [Line Items]
Income before income taxes																		1,367	3,399	5,413
Interest Rate Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of derivatives																			666
Interest Rate Contracts | Reclassification out of Accumulated Other Comprehensive Income
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense (income)																		88	135	154
Commodity Contract
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of derivatives																		(6,789)	5,064	(4,195)
Commodity Contract | Reclassification out of Accumulated Other Comprehensive Income
Derivative Instruments, Gain (Loss) [Line Items]
Production costs	[3]																	$ 1,279	$ 3,264	$ 5,259

[1] The company does not report gross margin. This line item presents our material, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately) under an alternative presentation.

[2] As disclosed in Note 4, Financial Statement Revisions, the company reported cash receipts and payments for the repurchase and sale of territories and cash paid at issuance of notes receivable at net when these transactions should have been disaggregated. We concluded that the errors were not material to any of these prior periods that were impacted. The error resulted in an understatement of cash flows from operating activities and cash flows used in investing activities of $5.9 million, $12.1 million and $12.8 million, respectively, for the sixteen, twenty-eight, and forty week amounts included in the first, second, and third quarters of fiscal 2017, respectively.  These amounts will be revised upon subsequent presentation of these financial statements.

[3] Included in Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately).