Stockholders' Equity (Schedule of Warrants Outstanding) (Details)	3 Months Ended
	Mar. 31, 2013
Class of Warrant or Right [Line Items]
Number of Warrants	2,743,050
Warrants exercised, shares issued	185,940
J [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	200,893
Exercise Price	6.16
Expiration Date	May 31, 2013
K [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	236,564
Exercise Price	9.60
Expiration Date	Apr. 01, 2013
Warrants exercised	131,250
L [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	6,250
Exercise Price	3.12
Expiration Date	Mar. 31, 2014
N [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	100,000
Exercise Price	6.25
Expiration Date	Feb. 22, 2015
O [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	230,900
Exercise Price	5.50
Expiration Date	Feb. 22, 2015
Warrants exercised	53,667
P [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	2,508
Exercise Price	6.25
Expiration Date	Feb. 16, 2015
Warrants exercised	2,187
Q [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	133,333
Exercise Price	5.50
Expiration Date	Feb. 22, 2015
R [Member]
Class of Warrant or Right [Line Items]
Number of Warrants	1,832,602
Exercise Price	9.90
Expiration Date	Jun. 22, 2016