Common Stock Warrants and Common Stock Warrant Liability (Tables)

12 Months Ended

Dec. 31, 2018

Warrants and Rights Note Disclosure [Abstract]

Schedule of common stock warrant activity

The table summarizes the common stock warrant activity as of December 31, 2018 as follows: 

Common Stock Warrants	Number  of Warrants			Date Issued	Term		Exercise Price
Outstanding at December 31, 2016		829,285
Common Stock Offering Warrants Issued		4,657,500		November 2017		5 years	$	1.50	(1)
Common Stock Offering Underwriter Warrants		945,000		November 2017		5 years	$	1.50
Outstanding at December 31, 2017		6,431,785
Warrants issued		1,133,909		June 2018		5 Years	$	1.82
Common Stock Offering Warrants Issued		5,357,052		August 2018		5 Years	$	1.15	(1)
Common Stock Offering - Dealer Manager Warrants		267,853		August 2018		5 Years	$	1.725
Warrants exercised		(1,475,659	)
Expired Warrants		(488,119	)
Outstanding at December 31, 2018		11,226,821

(1) The common stock warrants issued in November 2017 with an initial exercise price of $1.50 per share adjusted downward to $0.95 per share effective July 24, 2018 in connection with our Rights Offering, and may be subject to further downward adjustments, pursuant to antidilution price adjustment protection contained within those warrants.