Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 27, 2014	Dec. 28, 2013
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 52,000	$ 52,000
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, authorized shares	1,000,000	1,000,000
Preferred stock, issued shares	0	0
Ratio for converting shares of Class B common stock into shares of Class A common stock, numerator (in Class A shares)	1	1
Ratio for converting shares of Class B common stock into shares of Class A common stock, denominator (in Class B shares)	1	1
Treasury stock, shares	1,691,636	1,691,636
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, authorized shares	25,000,000	25,000,000
Common stock, issued shares	16,324,778	16,263,322
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, authorized shares	5,000,000	5,000,000
Common stock, issued shares	1,771,949	1,771,949