Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Marketable securities	$ 1,526	$ 695
Convertible note payable	3,408
Redeemable warrants	1,061	962
Level 1 [Member]
Marketable securities	1,526	695
Convertible note payable
Redeemable warrants
Level 2 [Member]
Marketable securities
Convertible note payable
Redeemable warrants
Level 3 [Member]
Marketable securities
Convertible note payable	3,408
Redeemable warrants	$ 1,061	$ 962