Stockholders' Equity (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 29,035,665
Net loss	(6,479,554)	(6,752,668)	(13,062,656)	(13,995,868)
Foreign currency translation gain (loss)	(80,543)	(18,160)	(4,040)	86,032
Stock based compensation			1,006,390
Public offering common stock, net			15,794,025
Balance	32,769,384		32,769,384
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			229,244
Balance (shares)			22,924,411
Net loss
Foreign currency translation gain (loss)
Stock based compensation			1,765
Stock based compensation (shares)			176,451
Public offering common stock, net			149,500
Public offering common stock, net (shares)			14,950,000
Balance	380,509		380,509
Balance (shares)	38,050,862		38,050,862
Additional Paid-in-Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			784,213,871
Net loss
Foreign currency translation gain (loss)
Stock based compensation			1,004,625
Public offering common stock, net			15,644,525
Balance	800,863,021		800,863,021
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			928,744
Net loss
Foreign currency translation gain (loss)			(4,040)
Stock based compensation
Public offering common stock, net
Balance	924,704		924,704
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(1,552,382)
Balance (shares)			165,906
Net loss
Foreign currency translation gain (loss)
Stock based compensation
Stock based compensation (shares)
Public offering common stock, net
Public offering common stock, net (shares)
Balance	(1,552,382)		(1,552,382)
Balance (shares)	165,906		165,906
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(754,783,812)
Net loss			(13,062,656)
Stock based compensation
Stock based compensation (shares)
Public offering common stock, net
Balance	$ (767,846,468)		$ (767,846,468)