Stock Authorization And Issuance (Details) (USD $)	3 Months Ended		9 Months Ended					1 Months Ended		0 Months Ended		1 Months Ended		1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 item Y	Sep. 30, 2011	Oct. 04, 2012	Oct. 03, 2012	Dec. 31, 2011	Jan. 31, 2009 First Shelf Registration Statement [Member]	Jan. 05, 2009 First Shelf Registration Statement [Member]	Sep. 19, 2012 Second Shelf Registration Statement [Member]	Apr. 18, 2012 Second Shelf Registration Statement [Member]	Sep. 30, 2009 Second Shelf Registration Statement [Member]	Sep. 14, 2009 Second Shelf Registration Statement [Member]	Sep. 30, 2012 Third Shelf Registration [Member]	Sep. 04, 2012 Third Shelf Registration [Member]
Stock Authorization And Issuance [Line Items]
Number of shelf registration statements filed			3
Offering period of various securities, in years			3
Securities offered under shelf registration statements, maximum amount									$ 25,000,000				$ 50,000,000		$ 25,000,000
Securities issued under shelf registration statements								19,600,000				36,700,000		10,100,000
Securities offering effective date								Jan. 20, 2009				Sep. 30, 2009		Sep. 11, 2012
Securities offering exipration								January 2012				September 2012
Sale of common stock, number of shares	82,862,796		82,862,796				67,573,775			4,381,761	8,139,050
Sale of stock price per share										$ 2.30	$ 1.05
Percentage of outstanding common stock on an after-issued basis										5.30%	10.70%
Net proceeds from issuance of common stock in public and private offerings	9,237,303	6,469,928	17,555,674	10,556,754						9,200,000	8,300,000
Shares of common stock issued upon exercise of warrants	605,827		2,214,658
Proceeds from warrants exercised	$ 400,000		$ 1,300,000
Common stock, shares authorized	100,000,000		100,000,000		150,000,000	100,000,000	100,000,000