Supplemental Consolidated Cash Flow Information (Additional Information Related To Cash Flows) (Details) - USD ($) $ in Thousands	4 Months Ended
	Jan. 17, 2021	Jan. 19, 2020
Supplemental Cash Flow Information [Abstract]
Decrease in obligations for treasury stock repurchases	$ 0	$ 2,025
Decrease in obligations for purchases of property and equipment	74	2,377
Increase in dividends accrued or converted to common stock equivalents	53	63
Right-of use assets obtained in exchange for operating lease obligations	40,266	51,311
Right-of use assets obtained in exchange for finance lease obligations	$ 65	$ 0