Basis of Presentation and Going Concern - Going Concern (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jul. 03, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Going Concern
Cash		$ 2,580,356	$ 12,982,748	$ 2,580,356	$ 12,982,748	$ 5,954,017	$ 10,551,721
Net cash used in operating activities				(7,009,701)	(9,464,217)
Net loss		(4,029,075)	$ 2,049,960	(6,719,563)	$ (5,568,666)
Working capital		$ (2,300,000)		$ (2,300,000)
Subsequent event
Going Concern
Sale of shares (in shares)	10,826
Exercise price of warrants (in dollars per share)	$ 1.55
Proceeds from rights offering	$ 9,900,000
Warrants | Subsequent event
Going Concern
Warrants issued (in shares)	6,224,950
Series C Preferred Stock | Subsequent event
Going Concern
Sale of shares (in shares)	10,826