Accrued Expenses and Warrant Liability - Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Compensation	$ 336	$ 1,233
Other	58	70
Total	$ 394	$ 1,303

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Period Type:	instant