Fair Value Measurements - Schedule of Fair Value of Liabilities on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Total fair value	$ 11,596	$ 64,687	$ 1,437
Warrant Derivative Liability [Member]
Total fair value	3,558	16,492	1,437
Debt Derivative Liability [Member]
Total fair value	8,038	48,195
Fair Value, Inputs, Level 1 [Member]
Total fair value
Fair Value, Inputs, Level 1 [Member] \| Warrant Derivative Liability [Member]
Total fair value
Fair Value, Inputs, Level 1 [Member] \| Debt Derivative Liability [Member]
Total fair value
Level 2 [Member]
Total fair value
Level 2 [Member] \| Warrant Derivative Liability [Member]
Total fair value
Level 2 [Member] \| Debt Derivative Liability [Member]
Total fair value
Level 3 [Member]
Total fair value	11,596	64,687
Level 3 [Member] \| Warrant Derivative Liability [Member]
Total fair value	3,558	16,492
Level 3 [Member] \| Debt Derivative Liability [Member]
Total fair value	$ 8,038	$ 48,195