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Reporting Segment Information - Summary of Sales by Type of Similar Products and Services (Detail) - USD ($) $ in Thousands	3 Months Ended						4 Months Ended		12 Months Ended
	Dec. 30, 2017	Oct. 07, 2017	Jul. 15, 2017	Dec. 31, 2016	Oct. 08, 2016	Jul. 16, 2016	Apr. 22, 2017	Apr. 23, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Revenue from External Customer [Line Items]
Consolidated net sales	$ 1,924,225	$ 1,906,644	$ 1,894,709	$ 1,828,183	$ 1,800,085	$ 1,827,562	$ 2,402,504	$ 2,278,770	$ 8,128,082	$ 7,734,600	$ 7,651,973
Sales Revenue [Member] | Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Consolidated net sales, Percentage									100.00%	100.00%	100.00%
Fuel [Member]
Revenue from External Customer [Line Items]
Consolidated net sales									$ 126,674	$ 110,619	$ 122,004
Fuel [Member] | Sales Revenue [Member] | Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Consolidated net sales, Percentage									1.60%	1.40%	1.60%
Center Store [Member]
Revenue from External Customer [Line Items]
Consolidated net sales									$ 4,877,289	$ 4,908,142	$ 4,845,763
Center Store [Member] | Sales Revenue [Member] | Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Consolidated net sales, Percentage									60.00%	63.50%	63.30%
Fresh [Member]
Revenue from External Customer [Line Items]
Consolidated net sales									$ 2,771,942	$ 2,359,829	$ 2,373,829
Fresh [Member] | Sales Revenue [Member] | Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Consolidated net sales, Percentage									34.10%	30.50%	31.00%
Pharmacy [Member]
Revenue from External Customer [Line Items]
Consolidated net sales									$ 352,177	$ 356,010	$ 310,377
Pharmacy [Member] | Sales Revenue [Member] | Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Consolidated net sales, Percentage									4.30%	4.60%	4.10%

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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