Net Income Per Common Share Data (Details 1) (Stock options [Member])
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Stock options [Member]
       
Schedule of equivalent shares that were excluded from the calculation of diluted net income per share because their effect would have been anti-dilutive        
Antidilutive equity awards 132,850    132,850 2,054,748