Term Loan - Schedule of Outstanding Loan and Unamortized Debt Discount Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Less: current portion	$ (15,676)	$ (4,650)
Loan payable, long-term		10,889
Term Loan [Member]
Debt Instrument [Line Items]
Term loan	15,500	15,500
Accrued portion of final payment fee	493	411
Less: unamortized discount on loan	(317)	(372)
Less: current portion	$ (15,676)	(4,650)
Loan payable, long-term		$ 10,889

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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Accrued portion of final payment fee.

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