Common Stock Warrants and Common Stock Warrant Liability (Details) - $ / shares		6 Months Ended	12 Months Ended
		Jun. 30, 2020	Dec. 31, 2019
Outstanding at beginning		489,176	561,343
Warrants issued
Outstanding at ending		2,504,597	489,176
Various [Member]
Issue Date		2016 and prior
Term Date		Various-2020/2021
Outstanding at beginning		17,059	17,059
Warrants issued
Warrants Exercised		(9,375)
Warrants Expired		(750)
Outstanding at ending		6,934	17,059
Common Stock Offering Warrants [Member]
Issue Date		November 21, 2017
Term Date		November 21, 2022
Exercise Price	[1]	$ 2.1122
Outstanding at beginning		143,501	159,092
Warrants issued
Warrants Exercised			(15,591)
Warrants Expired
Outstanding at ending		143,501	143,501
Dealer Manager Warrants [Member]
Issue Date		November 21, 2017
Term Date		November 21, 2022
Exercise Price		$ 30.00
Outstanding at beginning		47,250	47,250
Warrants issued
Warrants Exercised		(47,250)
Warrants Expired
Outstanding at ending			47,250
Warrant Reissue [Member]
Issue Date		June 20, 2018
Term Date		December 20, 2023
Exercise Price		$ 36.40
Outstanding at beginning		56,696	56,696
Warrants issued
Warrants Exercised
Warrants Expired
Outstanding at ending		56,696	56,696
Rights Offering Warrants [Member]
Issue Date		August 13, 2018
Term Date		July 25, 2023
Exercise Price		$ 23.00
Outstanding at beginning		202,943	267,853
Warrants issued
Warrants Exercised			(64,910)
Warrants Expired
Outstanding at ending		202,943	202,943
Dealer Manager Warrants [Member]
Issue Date		August 13, 2018
Term Date		August 13, 2023
Exercise Price		$ 34.50
Outstanding at beginning		13,393	13,393
Warrants issued
Warrants Exercised
Warrants Expired
Outstanding at ending		13,393	13,393
Dealer Manager Warrants [Member]
Issue Date		July 16, 2019
Term Date		July 11, 2024
Exercise Price		$ 33.75
Outstanding at beginning		8,334	8,334
Warrants issued
Warrants Exercised
Warrants Expired
Outstanding at ending		8,334	8,334
Registered Direct Offering [Member]
Issue Date		January 28, 2020
Term Date		July 28, 2025
Exercise Price		$ 9.00
Warrants issued		$ 177,500
Warrants Exercised
Warrants Expired
Outstanding at ending		177,500
Dealer Manager Warrants [Member]
Issue Date		January 28, 2020
Term Date		July 28, 2025
Exercise Price		$ 10.00
Warrants issued		$ 13,315
Warrants Exercised
Warrants Expired
Outstanding at ending		13,315
Registered Direct Offering [Member]
Issue Date		March 6, 2020
Term Date		September 8, 2025
Exercise Price		$ 2.88
Warrants issued		$ 176,372
Warrants Exercised
Warrants Expired
Outstanding at ending		176,372
Dealer Manager Warrants [Member]
Issue Date		March 6, 2020
Term Date		March 4, 2025
Exercise Price		$ 3.76
Warrants issued		$ 13,228
Warrants Exercised
Warrants Expired
Outstanding at ending		13,228
Dealer Manager Warrants [Member]
Issue Date		April 21, 2020
Term Date		April 21, 2025
Exercise Price		$ 3.97
Warrants issued		$ 118,073
Warrants Exercised
Warrants Expired
Outstanding at ending		118,073
Registered Direct Offering [Member]
Issue Date		April 24, 2020
Term Date		April 24, 2025
Exercise Price		$ 3.05
Warrants issued		$ 1,574,308
Warrants Exercised
Warrants Expired
Outstanding at ending		1,574,308

[1] Pursuant to antidilution price adjustment protection contained within these warrants, the initial exercise price of these warrants was $30.00 per share, which adjusted downward to $29.40 on July 24, 2018, the record date of the Right's Offering, downward to $19.00 per share on August 13, 2018, the date of the Rights Offering, downward to $7.13 per share on January 28, 2020, the date of a Registered Direct Offering and downward to $2.1122 per share on March 6, 2020, the date of a Registered Direct Offering.