Stockholders' Equity (Details 1) (USD $)	3 Months Ended
	Mar. 31, 2013
Summary of stock option activity
Number of Shares, Outstanding at beginning of period	4,279,919
Weighted Average Exercise Price Per Share, Outstanding at beginning of period	$ 3.70
Number of Shares, Granted	0
Number of Shares, Exercised
Weighted average Exercise Price Per Share, Exercised
Number of Shares, Forfeitures	(183,431)
Weighted Average Exercise Price Per Share, Forfeitures	$ 2.50
Number of Shares, Outstanding at end of period	4,212,730
Weighted Average Exercise Price Per Share, Outstanding at end of period	$ 3.77
Aggregate Intrinsic Value, Outstanding at end of period	$ 3,958,862
Officers and Directors [Member]
Summary of stock option activity
Number of Shares, Granted
Weighted Average Exercise Price Per Share, Granted
Others [Member]
Summary of stock option activity
Number of Shares, Granted	116,242
Weighted Average Exercise Price Per Share, Granted	$ 4.41