Restructuring Costs (Details) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2017
Restructuring Costs
Reduction in workforce (as a percent)	40.00%
Restructuring expense			$ 2,300,000
Accrual balance	$ 1,004,700	$ 1,004,700	405,936
Restructuring Reserve [Roll Forward]
Balance at beginning of period		1,004,700
Charges during the period			2,103,000
Amounts paid during the period		(598,764)	(1,697,064)
Balance at end of period	1,004,700	405,936	405,936
Employee Termination Accrual
Restructuring Costs
Accrual balance	181,500	181,500
Restructuring Reserve [Roll Forward]
Balance at beginning of period		181,500
Charges during the period			1,029,400
Amounts paid during the period		(181,500)	(1,029,400)
Balance at end of period	181,500
EC1456 Phase 1 Trial Termination Accrual
Restructuring Costs
Accrual balance	778,100	778,100	368,336
Restructuring Reserve [Roll Forward]
Balance at beginning of period		778,100
Charges during the period			947,100
Amounts paid during the period		(409,764)	(578,764)
Balance at end of period	778,100	368,336	368,336
Other Restructuring Costs Accrual
Restructuring Costs
Accrual balance	45,100	45,100	37,600
Restructuring Reserve [Roll Forward]
Balance at beginning of period		45,100
Charges during the period			126,500
Amounts paid during the period		(7,500)	(88,900)
Balance at end of period	$ 45,100	$ 37,600	37,600
General and Administrative Expense
Restructuring Costs
Employee termination benefits			100,000
Research and Development Expense.
Restructuring Costs
Employee termination benefits			900,000
Remaining EC1456 phase 1b trial expenses, including site close-out expenses			900,000
Other Restructuring Costs			300,000
Fixed asset impairment			$ 100,000