Schedule II - Valuation and Qualifying accounts (Details) - Allowance for Doubtful Accounts [Member] - USD ($)		12 Months Ended
		Dec. 29, 2018	Dec. 30, 2017
Valuation and qualifying accounts information [Abstract]
Balance at Beginning of Period		$ 470,000	$ 430,000
Charged to Costs and Expenses		220,000	87,000
Charged to Other Accounts - Describe		0	64,000
Deductions - Describe	[1]	10,000	111,000
Balance at End of Period		$ 680,000	$ 470,000

[1] Uncollectible accounts written off, net of recoveries.