Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2011	Dec. 31, 2010
ASSETS
Allowance for doubtful accounts for trade accounts receivable	$ 68,477	$ 71,689
Stockholders' equity
Common stock, par value	$ 0.01	$ 0.01
Common stock, share authorized	47,166,666	47,166,666
Common stock, share issued	29,178,271	29,178,271
Treasury stock, shares	140,250	140,250