XML 23 R67.htm IDEA: XBRL DOCUMENT v2.4.0.6
Customer Concentration - Additional Information (Detail) (USD $)
3 Months Ended 6 Months Ended
Jun. 30, 2012
Customer
Jun. 30, 2011
Customer
Jun. 30, 2012
Customer
Jun. 30, 2011
Customer
Dec. 31, 2011
Concentration Risk [Line Items]          
Number of customers with sales and accounts receivable concentration 5 5 5 5  
Due from top customers $ 41,297,358   $ 41,297,358   $ 21,919,828
Top Five Customers
         
Concentration Risk [Line Items]          
Due from top customers $ 19,888,840 16,417,668 $ 19,888,840 16,417,668  
Sales Revenue, Goods, Net
         
Concentration Risk [Line Items]          
Percentage of products sold to top five customers 42.80% 40.80% 43.40% 43.90%