Stock-Based Compensation (Details 2) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Schedule of stock options activity
Beginning outstanding balance	3,155,631	3,267,838
Granted	877,500	425,150
Exercised	(273,957)	(231,403)
Forfeited and cancelled	(21,000)	(305,954)
Ending outstanding balance	3,738,174	3,155,631
Aggregate intrinsic value of options exercised	$ 872,353	$ 443,000
Weighted average fair value of options granted	$ 5.31	$ 3.35