Term Loan - Schedule of Outstanding Loan and Unamortized Debt Discount Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Term loan	$ 15,500
Less: current portion	(2,067)
Loan payable, long-term	13,202	$ 15,014
Term Loans[Member]
Debt Instrument [Line Items]
Term loan	15,500	15,500
Less: unamortized discount on loan	(487)	(600)
Less: current portion	(2,067)
Accrued portion of final payment fee	256	114
Loan payable, long-term	$ 13,202	$ 15,014

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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