Stock-Based Compensation (Details 3) (Warrant [Member], USD $)	9 Months Ended
	Sep. 30, 2013
Warrant [Member]
Summary of all stock option plans / warrant activity
Number of Options/Warrants Outstanding, Beginning Balance	4,704,636
Warrants, Issued
Warrants, Expired/forfeited
Number of Options/Warrants Outstanding, Exercised	(3,871,063)
Number of Options/Warrants Outstanding, Ending Balance	833,573
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 1.61
Weighted Average Exercise Price, Issued
Weighted Average Exercise Price, Expired/forfeited
Weighted Average Exercise Price, Exercised	$ 1.45
Weighted Average Exercise Price, Outstanding, Ending Balance	$ 2.40
Weighted Average Remaining Contractual Life, Outstanding and exercisable	1 year 4 months 28 days
Weighted Average Remaining Contractual Life, Issued
Weighted Average Remaining Contractual Life, Expired/forfeited
Weighted Average Remaining Contractual Life, Exercised	2 years 3 months 22 days