Debt - Summary of Future Principal Payments (Details) - SVB and WestRiver $ in Thousands	Mar. 31, 2020 USD ($)
Debt Instrument [Line Items]
2020 (remaining nine months)	$ 2,528
2021	5,316
2022	5,677
2023	1,479
Thereafter	0
Total	15,000
Less unamortized loan fees	(256)
Total term loan borrowings	$ 14,744

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 of unamortized debt discount (premium) and debt issuance costs.

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

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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