BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
SHAREHOLDERS' EQUITY
Common stock, par value	$ 0	$ 0
Common stock, authorized shares	10,000,000	10,000,000
Common stock, issued shares	4,800,008	4,802,708
Common stock, outstanding shares	4,800,008	4,802,708
Common stock held in treasury	92,969	90,269