Stockholders' Equity and Convertible Preferred Stock (Details 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total compensation expense	$ 109	$ 98	$ 115	$ 286
Restricted Stock [Member] | Employee Restricted Stock Awards [Member]
Total compensation expense		27		107
Stock Option [Member] | Employee [Member]
Total compensation expense	2	71	8	179
Warrant [Member] | Non - Employee [Member]
Total compensation expense	$ 107		$ 107