Basic and Diluted Earnings per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended										4 Months Ended				12 Months Ended
	Dec. 29, 2018	Oct. 06, 2018	[1]	Jul. 14, 2018	[1]	Dec. 30, 2017	Oct. 07, 2017	[1]	Jul. 15, 2017	[1]	Apr. 21, 2018	[1]	Apr. 22, 2017	[1]	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 20,841	$ 39,630		$ 45,442		$ 78,533	$ (33,571)		$ 44,740		$ 51,247		$ 60,418		$ 157,160	$ 150,120	$ 163,776
Basic Earnings Per Common Share:
Basic weighted average shares outstanding per common share															211,016	209,573	208,511
Basic earnings per common share	$ 0.10	$ 0.19		$ 0.22		$ 0.37	$ (0.16)		$ 0.21		$ 0.24		$ 0.29		$ 0.74	$ 0.72	$ 0.79
Diluted Earnings Per Common Share:
Basic weighted average shares outstanding per common share															211,016	209,573	208,511
Add: Shares of common stock assumed issued upon exercise of stock options, vesting of performance-contingent restricted stock and deferred stock															616	862	1,843
Diluted weighted average shares outstanding per common share															211,632	210,435	210,354
Diluted earnings per common share	$ 0.10	$ 0.19		$ 0.21		$ 0.37	$ (0.16)		$ 0.21		$ 0.24		$ 0.29		$ 0.74	$ 0.71	$ 0.78

[1] 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.