Warrant Liabilities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Gain on warrant liabilities	$ 1,367,777	$ 3,827,617	$ 4,437,628
Warrants issued (in shares)	1,200,000	4,800,000
Exercised (in shares)	900,000
Warrant [Member]
Derivative [Line Items]
Risk-free interest rate	1.53%	0.90%	0.57%
Expected dividend yield	0.00%	0.00%	0.00%
Expected lives	6 months 18 days	1 year 2 months 23 days	7 months 2 days
Expected volatility	96.70%	119.10%	61.70%
Warrants classified as liabilities (in shares)	2,834,246	4,752,512	1,061,976
Gain on warrant liabilities	$ 1,367,777	$ 3,827,617	$ 4,437,628
Exercised (in shares)	900,000