INCOME TAXES (Details 1) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Loss before income taxes, as reported in the consolidated statements of operations	$ (118,476,012)	$ (78,252,894)	$ (62,948,646)
Computed "expected" tax benefit	(40,281,844)	(26,605,984)	(21,402,540)
Increase (decrease) in income taxes resulting from:
Expected benefit from state and local taxes	(1,105,708)	(835,072)	(672,306)
Research and development credits	(3,697,258)	(2,364,417)	(1,603,364)
Other	1,563,114	(7,506)	566,310
Impact of change in state tax rates on deferred taxes	0	0	5,836,819
Stock awards	8,213,188	0	0
Effects of federal tax reform rate changes	51,767,584	0	0
Change in the balance of the valuation allowance for deferred tax assets	(16,459,076)	29,812,979	17,275,081
Income Tax Expense (Benefit)	$ 0	$ 0	$ 0

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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