Statements of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Preferred Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]	Series A Preferred Stock [Member]	Series A Preferred Stock [Member] Common Stock [Member]	Series A Preferred Stock [Member] Preferred Stock [Member]	Series A Preferred Stock [Member] Additional Paid-in Capital [Member]	Series B-1 Preferred Stock [Member]	Series B-1 Preferred Stock [Member] Common Stock [Member]	Series B-1 Preferred Stock [Member] Preferred Stock [Member]	Series B-1 Preferred Stock [Member] Additional Paid-in Capital [Member]
Balance, value at Oct. 17, 2005	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Balance, shares at Oct. 17, 2005		0	0
Proceeds from sale of stock, shares		972,000
Proceeds from sale of stock	38,880	97		38,783
Founders stock	933,120			933,120
Stock based compensation	26,004			26,004
Components of comprehensive loss
Net loss	(1,207,234)				(1,207,234)
Balance, value at Dec. 31, 2005	(209,230)	97	0	997,907	(1,207,234)	0
Balance, shares at Dec. 31, 2005		972,000	0
Transfer of assets at historical cost (1/06 @ $0.03 per share), shares		1,028,000
Transfer of assets at historical cost (1/06 @ $0.03 per share)	31,200	103		31,097
Proceeds from IPO (7/06 @ $5.50 per unit), shares		3,000,000
Proceeds from IPO (7/06 @ $5.50 per unit)	16,500,000	300		16,499,700
Issuance costs	(2,392,071)			(2,392,071)
Stock issued to bridge loan lenders (7/06 @ $2.75 per share), shares		290,894
Stock issued to bridge loan lenders (7/06 @ $2.75 per share)	800,000	29		799,971
Exercise of stock options, shares		31,200
Exercise of stock options	3,120	3		3,117
Stock based compensation	348,943			348,943
Components of comprehensive loss
Net loss	(4,180,912)				(4,180,912)
Balance, value at Dec. 31, 2006	10,901,050	532	0	16,288,664	(5,388,146)	0
Balance, shares at Dec. 31, 2006		5,322,094	0
Exercise of stock options, shares		169,963
Exercise of stock options	346,434	17		346,417
Conversion of shares, shares		3,098,382
Conversion of shares	20,449,321	310		20,449,011
Redemption of Class A public warrants at $0.25 per share	(48,128)			(48,128)
Conversion of Class B public warrants at $11.00, shares		11,000
Conversion of Class B public warrants at $11.00 per share	121,000	1		120,999
Stock based compensation	1,734,879			1,734,879
Proceeds from private placement:
Common stock, shares		2,534,462
Common stock	15,962,257	254		15,962,003
Proceeds from private placement: Class B public warrants (3/08 @ $3.954)	3,754,468			3,754,468
Private placement costs	(75,807)			(75,807)
Exercise of representative's warrants, shares		300,000
Exercise of representative's warrants	1,980,000	30		1,979,970
Components of comprehensive loss
Net loss	(6,503,419)				(6,503,419)
Balance, value at Dec. 31, 2007	48,622,055	1,144	0	60,512,476	(11,891,565)	0
Balance, shares at Dec. 31, 2007		11,435,901	0
Exercise of stock options, shares		133,137
Exercise of stock options	120,533	13		120,520
Issuance of Restricted Stock, shares		69,846
Issuance of Restricted Stock	0	7		(7)
Conversion of Class B public warrants at $11.00, shares		98,800
Conversion of Class B public warrants at $11.00 per share	1,086,800	10		1,086,790
Stock based compensation	1,881,399			1,881,399
Proceeds from private placement:
Common stock, shares		4,763,698
Common stock	36,647,693	476		36,647,217
Proceeds from private placement: Class B public warrants (3/08 @ $3.954)	6,681,884			6,681,884
Exercise of representative's warrants, shares		75,000
Exercise of representative's warrants	495,000	8		494,992
Proceeds from shareholder under Section 16(b)	148,109			148,109
Proceeds from secondary public offering, shares		4,370,000
Proceeds from secondary public offering (5/08 @ $14.00)	61,180,000	437		61,179,563
Costs of secondary public offering	(4,361,358)			(4,361,358)
Components of comprehensive loss
Unrealized gain (loss) on investments	331,068					331,068
Net loss	(13,215,076)				(13,215,076)
Net Loss	(12,884,008)
Balance, value at Dec. 31, 2008	139,618,107	2,095	0	164,391,585	(25,106,641)	331,068
Balance, shares at Dec. 31, 2008		20,946,382	0
Exercise of stock options, shares		105,169
Exercise of stock options	339,616	10		339,606
Issuance of Restricted Stock, shares		147,679
Issuance of Restricted Stock		15		(15)
Stock based compensation	2,676,957			2,676,957
Proceeds from private placement:
Common stock, shares		769,230
Common stock	4,999,995	77		4,999,918
Proceeds from public offering, shares		4,615,385
Proceeds from public offering	30,000,003	461		29,999,542
Costs of public offering	(2,062,866)			(2,062,866)
Components of comprehensive loss
Unrealized gain (loss) on investments	(334,080)					(334,080)
Net loss	(20,922,717)				(20,922,717)
Net Loss	(21,256,797)
Balance, value at Dec. 31, 2009	154,315,015	2,658	0	200,344,727	(46,029,358)	(3,012)
Balance, shares at Dec. 31, 2009		26,583,845	0
Exercise of stock options, shares		161,330
Exercise of stock options	391,001	16		390,985
Issuance of Restricted Stock, shares		270,412
Issuance of Restricted Stock	0	27		(27)
Stock based compensation	2,713,468			2,713,468
Proceeds from private placement:
Proceeds from public offering, shares		5,250,000
Proceeds from public offering	21,787,500	525		21,786,975
Costs of public offering	(1,409,937)			(1,409,937)
Components of comprehensive loss
Unrealized gain (loss) on investments	2,786					2,786
Net loss	(31,233,718)				(31,233,718)
Net Loss	(31,230,932)
Balance, value at Dec. 31, 2010	146,566,115	3,226	0	223,826,191	(77,263,076)	(226)
Balance, shares at Dec. 31, 2010		32,265,587	0
Exercise of stock options, shares	57	57,000
Exercise of stock options	5,700	6		5,694
Issuance of Restricted Stock, shares		191,822
Issuance of Restricted Stock	0	19		(19)
Issuance of common stock to service provider, shares		45,000
Issuance Of Common Stock To Service Provider, Value	58,950	5		58,945
Stock based compensation	1,572,607			1,572,607
Proceeds from private placement:
Common stock, shares		6,400,000
Common stock	7,360,000	640		7,359,360
Private placement costs	(123,973)			(123,973)
Net Proceeds from At-The-Market offering sales, shares		386,050
Net Proceeds from At-The-Market offering sales	305,784	39		305,745
Proceeds from shareholder under Section 16(b)	0
Components of comprehensive loss
Unrealized gain (loss) on investments	1,245					1,245
Net loss	(105,743,860)				(105,743,860)
Net Loss	(105,742,615)
Balance, value at Dec. 31, 2011	50,002,568	3,935	0	233,004,550	(183,006,936)	1,019
Balance, shares at Dec. 31, 2011		39,345,459	0
Exercise of stock options, shares	14	13,750
Exercise of stock options	9,350	1		9,349
Issuance of Restricted Stock, shares		645,816
Issuance of Restricted Stock	0	65		(65)
Stock based compensation	924,315			924,315
Proceeds from private placement:
Common stock, shares		9,166,700
Common stock	11,000,039	916		10,999,123
Private placement costs	(836,697)			(836,697)
Net Proceeds from At-The-Market offering sales, shares		1,972,181
Net Proceeds from At-The-Market offering sales	1,896,572	197		1,896,375
Proceeds from shareholder under Section 16(b)	0
Components of comprehensive loss
Unrealized gain (loss) on investments	(1,019)					(1,019)
Net loss	(28,768,398)				(28,768,398)
Net Loss	(28,769,417)
Balance, value at Dec. 31, 2012	34,226,730	5,114	0	245,996,950	(211,775,334)	0			0				0
Balance, shares at Dec. 31, 2012		51,143,906	0						0
Proceeds from sale of stock, shares									750,000				500
Proceeds from sale of stock							6,000,000		75	5,999,925	5,000,000			5,000,000
Issuance costs							(139,894)			(139,894)	(72,589)			(72,589)
Exercise of stock options, shares	48	47,500
Exercise of stock options	32,300	5		32,295
Issuance of Restricted Stock, shares		467,908
Issuance of Restricted Stock	0	47		(47)
Issuance of common stock to service provider, shares		240,000
Issuance Of Common Stock To Service Provider, Value	142,999	24		142,975
Conversion of shares, shares								4,872,736	(387,610)			2,476,474	(150)
Conversion of shares							919,622	487	(39)	919,174	924,146	248		923,898
Stock based compensation	621,505			621,505
Proceeds from private placement:
Common stock, shares		2,500,000
Common stock	1,425,000	250		1,424,750
Proceeds from private placement: Class B public warrants (3/08 @ $3.954)							1,071,063			1,071,063
Proceeds from shareholder under Section 16(b)	0
Discount on Preferred Stock issuance - beneficial conversion feature							1,350,000			1,350,000
Deemed dividends on preferred stock and accretion of warrants	(5,935,762)				(5,935,762)
Components of comprehensive loss
Net loss	(30,130,951)				(30,130,951)
Net Loss	(30,130,951)
Balance, value at Dec. 31, 2013	$ 15,434,169	$ 6,175		$ 263,270,005	$ (247,842,047)				$ 36				$ 0
Balance, shares at Dec. 31, 2013		61,748,524							362,390				350