Accrued Expenses and Long-term Liabilities - Schedule of Long Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Warrant liability	$ 82	$ 361
Uncertain tax positions	4,081	3,838
Deferred revenue	269
Other	141	120
Total other long-term liabilities	$ 4,573	$ 4,319