Recent Accounting Pronouncements - Components of Net Periodic Pension and Postretirement Benefits Credit (Detail) - USD ($) $ in Thousands	3 Months Ended												4 Months Ended				12 Months Ended
	Dec. 29, 2018	[1]	Oct. 06, 2018	[1],[2]	Jul. 14, 2018	[1],[2]	Dec. 30, 2017	[1]	Oct. 07, 2017	[1],[2]	Jul. 15, 2017	[1],[2]	Apr. 21, 2018	[1],[2]	Apr. 22, 2017	[1],[2]	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately below)	$ 467,155		$ 485,680		$ 488,871		$ 456,895		$ 476,264		$ 468,246		$ 625,122		$ 608,068		$ 2,066,828	$ 2,009,473	$ 2,026,859
Selling, distribution and administrative expenses																	1,507,256	1,510,015	1,469,382
Income (Loss) from operations																	212,344	161,003	264,898
Other components of net periodic pension and postretirement benefits credit																	$ (529)	(6,558)	(5,638)
As reported
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately below)																		2,009,063	2,026,367
Selling, distribution and administrative expenses																		1,503,867	1,464,236
Income (Loss) from operations																		$ 162,912	$ 263,890

[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 were revised upon subsequent presentation of these financial statements.