Summary of Significant Accounting Policies (Schedule Of Costs For Closed Stores) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Closed store lease liabilities, Beginning Balance	$ 105
Closed store lease liabilities, Ending Balance	39	$ 105
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Closed store lease liabilities, Beginning Balance	105	212
Additions	0	0
Payments	0	(33)
Adjustments	(66)	(74)
Closed store lease liabilities, Ending Balance	$ 39	$ 105