Organization and Summary of Significant Accounting Policies - Disaggregated Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Disaggregation of Revenue [Line Items]
Sales	$ 764,082	$ 652,540	$ 2,327,819	$ 1,904,100
Perishable
Disaggregation of Revenue [Line Items]
Sales	258,923	223,329	788,190	651,758
Non-Perishable
Disaggregation of Revenue [Line Items]
Sales	$ 505,159	$ 429,211	$ 1,539,629	$ 1,252,342