Warrants (Schedule of Warrants Outstanding) (Details)	12 Months Ended
	Dec. 31, 2018 $ / shares shares
Warrants [Line Items]
No. outstanding	140,000	[1]
October 2015 Warrants [Member]
Warrants [Line Items]
No. outstanding	2,500	[1]
Exercise price | $ / shares	$ 100.00	[1]
Remaining contractual life	2 years 3 months 14 days
Expiration Date	April 15, 2021
December 2016 Warrants [Member]
Warrants [Line Items]
No. outstanding	125,000	[1]
Exercise price | $ / shares	$ 60.00	[1]
Remaining contractual life	2 years 11 months 23 days
Expiration Date	December 23, 2021
May 2018 Warrants [Member]
Warrants [Line Items]
No. outstanding	12,500	[1]
Exercise price | $ / shares	$ 12.40	[1]
Remaining contractual life	4 years 10 months 17 days
Expiration Date	November 17, 2023
May 2015 Warrants [Member]
Warrants [Line Items]
No. outstanding	26,875	[1]
Exercise price | $ / shares	$ 60.00	[1]
Remaining contractual life	1 year 4 months 2 days
Expiration Date	May 4, 2020

[1] Adjusted to reflect the impact of the 1:20 reverse stock split that became effective on February 22, 2019.