Consolidated Statements of Equity - USD ($)	Common Stock [Member]	Contingently Issuable Share [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2014	$ 44,974		$ 175,476,521	$ (234,337)	$ (95,185,280)	$ 80,101,884
Balance (in shares) at Dec. 31, 2014	44,974,248	6		41,309
Issuance of common stock in connection with exercise of warrants	$ 2,946		1,064,393			1,067,339
Issuance of common stock in connection with exercise of warrants (in shares)	2,946,703
Issuance of common stock in connection with cashless exercise of warrants	$ 3		(3)			0
Issuance of common stock in connection with cashless exercise of warrants (in shares)	2,915
Issuance of common stock in connection with conversion of notes payable	$ 1		6,924			6,925
Issuance of common stock in connection with conversion of notes payable (in shares)	522
Issuance of restricted stock	$ 1,993		(1,993)			0
Issuance of restricted stock (in shares)	1,992,535
Forfeiture of restricted stock	$ (31)		31			0
Forfeiture of restricted stock (in shares)	(31,166)
Issuance of common stock to related party for cash (See Note 9)	$ 115		749,890			750,005
Issuance of common stock to related party for cash (See Note 9) (in shares)	114,855
Compensation in respect of restricted stock granted to employees, directors and consultants			15,697,092			15,697,092
Issuance of common stock in At the Market offering	$ 4,094		66,894,609			66,898,703
Issuance of common stock in At the Market offering (in shares)	4,094,498
Net loss					(62,948,646)	(62,948,646)
Balance at Dec. 31, 2015	$ 54,095		259,887,464	$ (234,337)	(158,133,926)	101,573,302
Balance (in shares) at Dec. 31, 2015	54,095,110	6		41,309
Issuance of common stock in connection with exercise of warrants	$ 273		617,969			618,242
Issuance of common stock in connection with exercise of warrants (in shares)	273,370
Issuance of common stock in connection with conversion of notes payable	$ 4		33,013			33,017
Issuance of common stock in connection with conversion of notes payable (in shares)	3,710
Issuance of restricted stock	$ 1,925		(1,925)			0
Issuance of restricted stock (in shares)	1,924,639
Forfeiture of restricted stock	$ (47)		47			0
Forfeiture of restricted stock (in shares)	(46,773)
Issuance of common stock in At-the-Market offering (net of offering costs)	$ 570		4,385,566			4,386,136
Issuance of common stock in At-the-Market offering (net of offering costs) (in shares)	570,366
Compensation in respect of restricted stock granted to employees, directors and consultants			7,509,999			7,509,999
Adjustment to contingently issuable shares		$ (6)	6			0
Net loss					(78,252,894)	(78,252,894)
Balance at Dec. 31, 2016	$ 56,820	0	272,432,139	$ (234,337)	(236,386,820)	35,867,802
Balance (in shares) at Dec. 31, 2016	56,820,422			41,309
Issuance of common stock in connection with exercise of warrants	$ 888		2,142,197			2,143,085
Issuance of common stock in connection with exercise of warrants (in shares)	887,585
Issuance of restricted stock	$ 1,837		(1,837)
Issuance of restricted stock (in shares)	1,836,511
Forfeiture of restricted stock	$ (54)		54
Forfeiture of restricted stock (in shares)	(53,875)
Issuance of common stock in At-the-Market offering (net of offering costs)	$ 5,897		53,634,115			53,640,012
Issuance of common stock in At-the-Market offering (net of offering costs) (in shares)	5,897,436
Compensation in respect of restricted stock granted to employees, directors and consultants			15,945,284			15,945,284
Issuance of common stock in At the Market offering	$ 7,794		77,865,090			77,872,884
Issuance of common stock in At the Market offering (in shares)	7,793,671
Net loss					(118,476,012)	(118,476,012)
Balance at Dec. 31, 2017	$ 73,182	$ 0	$ 422,017,042	$ (234,337)	$ (354,862,832)	$ 66,993,055
Balance (in shares) at Dec. 31, 2017	73,181,750			41,309