Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0017	$ 0.0017
Common stock, shares authorized	16,000,000	16,000,000
Common stock, shares issued	8,061,000	8,030,000
Common stock, shares outstanding	7,594,000	7,890,000
Treasury stock, shares	332,000	140,000