Earnings Per Share (Details 2) - $ / shares		1 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2015	Jan. 31, 2014	Feb. 28, 2013	May. 31, 2011	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	May. 31, 2014
Dilutive potential common shares
Stock options outstanding	11,789,611				11,789,611	7,267,404	11,789,611	7,267,404
Restricted stock outstanding	395,558				395,558	433,336	395,558	433,336
Common stock warrants	4,192,567				4,192,567	4,219,442	4,192,567	4,219,442
Preferred stock	5,554,594				5,554,594	5,554,594	5,554,594	5,554,594
Number of dilutive potential common shares	21,932,330				21,932,330	17,474,776	21,932,330	17,474,776
Earnings Per Share
Weighted average exercise price							$ 3.86
Preferred stock	5,554,594				5,554,594	5,554,594	5,554,594	5,554,594
Stock options
Earnings Per Share
Stock options granted					3,270,000	2,454,000	3,920,000	3,140,000
Warrants issued in May, 2011
Earnings Per Share
Number of warrants issued (in shares)				7,128,563
Antidilutive shares excluded from calculation of diluted earnings per share				22,995,365
Number of warrants unexercised (in shares)							192,467	219,349
Warrants issued in February, 2013
Earnings Per Share
Number of warrants issued (in shares)			23,637,500
Number of warrants unexercised (in shares)							100	100
Warrants issued in January, 2014
Earnings Per Share
Number of warrants issued (in shares)		4,000,000
Number of warrants unexercised (in shares)							4,000,000	4,000,000
Series C redeemable convertible preferred stock
Dilutive potential common shares
Preferred stock									10,431
Earnings Per Share
Preferred stock									10,431
Number of preferred shares that had been converted to common stock	5,200