Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Balance Sheets [Abstract]
Trade accounts receivable, allowance for doubtful accounts	$ 78,000	$ 76,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	12,000,000	12,000,000
Common stock, shares issued	8,983,374	8,914,274