Debt - Carrying Value (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Debt
Net carrying value of debt, Current Portion	$ 649	$ 3,884
Net carrying value of debt, Long-term debt	11,345	4,218
2015 Credit Facility
Debt
Debt, including end of term fee, Current Portion		4,054
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Current Portion		(177)
Net carrying value of debt, Current Portion		3,877
Debt, including end of term fee, Long-term debt		4,301
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Long-term debt		(83)
Net carrying value of debt, Long-term debt		4,218
Debt, including end of term fee, Total		8,355
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Total		(260)
Net carrying value of debt, Total		$ 8,095
2017 Credit Facility
Debt
Debt, including end of term fee, Current Portion	667
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Current Portion	(18)
Net carrying value of debt, Current Portion	649
Debt, including end of term fee, Long-term debt	12,053
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Long-term debt	(708)
Net carrying value of debt, Long-term debt	11,345
Debt, including end of term fee, Total	12,720
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Total	(726)
Net carrying value of debt, Total	$ 11,994