CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - USD ($)	Mar. 31, 2018	Dec. 30, 2017
Current Assets
Accounts receivable, allowances	$ 477,000	$ 389,000
Shareholders' Equity
Preferred Stock, par value (in dollars per share)	$ 0	$ 0
Preferred Stock, shares authorized (in shares)	2,000,000	2,000,000
Common Stock, par value (in dollars per share)	$ 0	$ 0
Common Stock, shares authorized (in shares)	50,000,000	50,000,000
Common Stock, shares issued (in shares)	8,959,729	8,957,974
Treasury Stock, shares (in shares)	2,694,729	2,694,729