Senior Convertible Notes and Warrants (Schedule of carrying value of Notes and Warrants) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Liability component:
Principal		$ 3,000
Less: debt discount and issuance costs, net of amortization		(778)
Net carrying amount		2,222
Equity component:
Warrants	[1]	318
Conversion feature	[1]	122
Net carrying amount	[1]	$ 440

[1] Recorded on the consolidated balance sheets as additional paid-in capital.