Accrued Expenses (Details) (USD $)
Sep. 30, 2012
Dec. 31, 2011
Payables and Accruals [Abstract]    
Accrued compensation $ 1,586,529 $ 1,710,448
Accrued rebates 1,960,699 1,557,081
Deferred rent 1,130,915 706,188
Other 2,248,737 1,221,828
Total accrued expenses $ 6,926,880 $ 5,195,545