Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 45,679,880	$ 2,119,646
Prepaid expenses	1,369,494	146,704
Total current assets	47,049,374	2,266,350
Property and equipment, net of accumulated depreciation of $273,092 in 2013 and $280,823 in 2014	11,997,697	11,963,079
Deferred financing costs, net	115,693	157,499
Prepaid expenses, long-term	1,677,434
Other assets	18,208	18,208
Total assets	60,858,406	14,405,136
Current liabilities:
Accounts payable	2,654,871	715,454
Accrued expenses	660,139	379,164
Loan payable, current portion	3,559,743	5,105,407
Warrant liability	365,914	644,478
Total current liabilities	7,240,667	6,844,503
Loan payable, long-term	11,241,442	9,769,528
Commitment and contingencies
Stockholders' (deficit) equity:
Preferred stock, $.0001 par value, authorized 10,000,000 shares; issued 0 shares outstanding at December 31, 2013 and September 30, 2014
Common stock, $.0001 par value, authorized 150,000,000 shares; issued 109,321 and outstanding 103,536 shares at December 31, 2013 and issued 18,598,754 and outstanding 18,592,968 shares at September 30, 2014	1,860	88
Additional paid-in capital	169,921,290	46,872,723
Accumulated deficit	(127,546,853)	(118,314,383)
Total stockholders' (deficit) equity	42,376,297	(71,441,572)
Total liabilities, convertible preferred stock and stockholders' (deficit) equity	60,858,406	14,405,136
Series A-1, 8%, non-cumulative convertible preferred stock
Current liabilities:
Convertible preferred stock		898,305
Series A-2 convertible preferred stock
Current liabilities:
Convertible preferred stock		543,623
Series B, 8% non-cumulative, convertible preferred stock
Current liabilities:
Convertible preferred stock		44,928,382
Series C, 12% non-cumulative, convertible preferred stock
Current liabilities:
Convertible preferred stock		$ 22,862,367