Stock Purchase Warrants (Details) - $ / shares	1 Months Ended		9 Months Ended	12 Months Ended
	Dec. 26, 2017	Nov. 18, 2016	Sep. 30, 2018	Dec. 31, 2017
Closing Stock Price [Member]
Closing stock price	$ 18.55	$ 61.25	$ 2.60	$ 17.85
Expected Dividends [Member]
Warrants, Measurement Input	0.00%	0.00%	0.00%	0.00%
Expected Volatility [Member]
Warrants, Measurement Input	85.00%	95.00%	90.00%	80.00%
Risk Free Interest Rate [Member]
Warrants, Measurement Input	2.42%	1.39%	2.60%	1.86%
Expected Life Of Warrant [Member]
Expected life of warrant (years)	4 years 11 months 1 day	5 years	1 year 14 days	1 year 9 months 14 days
Series A Warrants [Member] | Closing Stock Price [Member]
Closing stock price		$ 31.15	$ 2.60	$ 17.85
Series A Warrants [Member] | Expected Dividends [Member]
Warrants, Measurement Input		0.00%	0.00%	0.00%
Series A Warrants [Member] | Expected Volatility [Member]
Warrants, Measurement Input		85.00%	80.00%	80.00%
Series A Warrants [Member] | Risk Free Interest Rate [Member]
Warrants, Measurement Input		1.58%	2.82%	1.97%
Series A Warrants [Member] | Expected Life Of Warrant [Member]
Expected life of warrant (years)		4 years	2 years 1 month 20 days	2 years 10 months 24 days