Segments - Summary of Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2018	Apr. 02, 2017
Disaggregation Of Revenue [Line Items]
Net Sales, amount	$ 1,287,196	$ 1,130,645
Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]
Disaggregation Of Revenue [Line Items]
Net Sales, percentage	100.00%	100.00%
Perishables [Member]
Disaggregation Of Revenue [Line Items]
Net Sales, amount	$ 732,602	$ 649,434
Perishables [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]
Disaggregation Of Revenue [Line Items]
Net Sales, percentage	56.90%	57.40%
Non-Perishables [Member]
Disaggregation Of Revenue [Line Items]
Net Sales, amount	$ 554,594	$ 481,211
Non-Perishables [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]
Disaggregation Of Revenue [Line Items]
Net Sales, percentage	43.10%	42.60%