Common Stock Warrants and Common Stock Warrant Liability (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands							1 Months Ended		12 Months Ended
	Dec. 02, 2019	Jul. 31, 2019	Aug. 13, 2018	Jul. 24, 2018	Jun. 20, 2018	Nov. 21, 2017	Jun. 30, 2018	Jun. 30, 2015	Dec. 31, 2019	Dec. 31, 2018	Aug. 31, 2018
Common stock offering warrants issued
Share price (in dollars per share)									$ 11.00	$ 11.70
Fair value adjustment of warrants									$ 0	$ 1
Stock compensation expense									873	$ 3,413
Deemed dividend									333
Unexercised warrants									$ 159,093
Common stock warrants issued, description									Common stock warrants issued in November 2017 with an initial exercise price of $30.00 per share adjusted downward to $19.00 per share effective July 24, 2018.
University of Arizona Common Stock Warrant [Member]
Exercise price (in dollars per share)									$ 158.20
Description of method used									Monte Carlo option pricing model
Expected volatility rate									77.70%
Expected dividend rate									0.00%
Risk free interest rate									1.93%
Change in fair value of the derivative warrant liability									$ 0
University of Arizona Common Stock Warrant [Member] | License Agreement [Member]
Number of warrant purchased								750
Exercise price (in dollars per share)								$ 150.00
Warrant term								5 years
Change in fair value of the derivative warrant liability								$ 53
Common Stock Warrant Issued to Underwriter of Common Stock Offering [Member]
Exercise price (in dollars per share)			$ 19.00	$ 29.40
Share price (in dollars per share)			$ 20.40	$ 26.60
Expected volatility rate			74.00%	72.40%
Expected term			4 years 2 months 30 days	4 years 3 months 29 days
Expected dividend rate			0.00%	0.00%
Risk free interest rate			2.75%	2.83%
Common Stock Warrant Issued to Underwriter of Common Stock Offering [Member] | H.C. Wainwright & Co [Member]
Number of warrant purchased		8,334
Exercise price (in dollars per share)		$ 33.75
Exercisable price (in dollars per share)		$ 33.75
Warrant term		5 years
Share price (in dollars per share)		$ 26.80
Fair value of common stock warrant		$ 127
Expected volatility rate		133.30%
Expected term		5 years
Expected dividend rate		0.00%
Risk free interest rate		2.07%
Common Stock warrants issued [Member]
Number of warrant purchased					56,696	232,875	56,696
Exercise price (in dollars per share)					$ 36.40	$ 30.00	$ 36.40
Exercisable price (in dollars per share)						$ 30.00
Warrant term						5 years
Description of method used						Lattice model
Share price (in dollars per share)						$ 20.00	$ 42.20
Fair value of common stock warrant						$ 661
Expected volatility rate						73.80%	72.60%
Expected term						5 years	5 years
Expected dividend rate						0.00%	0.00%
Risk free interest rate						1.87%	2.80%
Proceeds from warrant exercises							$ 1,700
Stock compensation expense							$ 1,700
November 2017 warrants [Member]
Common stock offering warrants issued					56,696
Number of warrant purchased					56,696
Exercise price (in dollars per share)					$ 30.00
Proceeds from warrant exercises					$ 1,700
New Warrants November 8, 2017 [Member]
Number of warrant purchased							17,088
Proceeds from warrant exercises							$ 513
Deemed Dividend Adjustment Warrant Modified Terms Revaluation [Member]
Common stock offering warrants issued	6,934
Share price (in dollars per share)	$ 12.00
Expected volatility rate	73.20%
Expected term	1 year 4 days
Expected dividend rate	0.00%
Risk free interest rate	1.63%
Deemed dividend	$ 11
Unexercised warrants	$ 6,394
Dividend, description	New Enterprises between September 2015 and February 2016. Specifically, the original strike price was reduced to $20.00 per warrant from $150.00 per warrant and the expiration date of these warrants was extended one year to December 13, 2020.
Deemed Dividend Adjustment Warrant Modified Terms Revaluation [Member] | ASC 260 [Member]
Share price (in dollars per share)	$ 12.00
Expected volatility rate	73.20%
Expected term	4 days
Expected dividend rate	0.00%
Risk free interest rate	1.63%
Rights offering [Member]
Common stock offering warrants issued			267,853
Number of warrant purchased			13,393
Exercise price (in dollars per share)			$ 23.00								$ 23.00
Share price (in dollars per share)			$ 23.00
Fair value of common stock warrant			$ 3,600
Number of share issued in transaction			267,853
Rights offering [Member] | Monte Carlo model [Member]
Share price (in dollars per share)			$ 18.80
Expected volatility rate			159.00%
Expected term			5 years
Expected dividend rate			0.00%
Risk free interest rate			2.77%
Rights offering [Member] | Warrant [Member]
Exercise price (in dollars per share)											$ 34.50
Rights offering [Member] | Warrant [Member] | Maxim Partners LLC [Member]
Share price (in dollars per share)			$ 34.50
Fair value of common stock warrant			$ 169
Expected volatility rate			159.00%
Expected term			5 years
Expected dividend rate			0.00%
Risk free interest rate			2.77%
Rights offering [Member] | Warrant [Member] | Maxim Partners LLC [Member] | Monte Carlo model [Member]
Share price (in dollars per share)			$ 18.80
Expected volatility rate			159.00%
Expected term			5 years
Expected dividend rate			0.00%
Risk free interest rate			2.77%
Public Offering [Member]
Number of warrant purchased						293,000
Exercise price (in dollars per share)						$ 30.00