Amortization period of payments of principal plus interest amounts.

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Debt instrument prepayment fee percentage.

+ References

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Interest only period extended.

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Percentage of final payment on principal amount of refinanced advances.

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Date the warrants or rights are exercisable, in CCYY-MM-DD format.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

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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- Definition

The average effective interest rate during the reporting period.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Percentage of principal amount of debt redeemed.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Details) - USD ($)	1 Months Ended			3 Months Ended
Debt - Additional Information (Details) - USD ($)	Mar. 31, 2019	Nov. 30, 2017	Oct. 31, 2017	Mar. 31, 2020	Mar. 31, 2019	May 31, 2019
Silicon Valley Bank
Debt Instrument [Line Items]
Debt instrument, maturity date	Mar. 01, 2023
Percentage of final payment on principal amount of refinanced advances	6.00%				6.00%
Total term loan borrowings				$ 300,000
Silicon Valley Bank \| Tranche 1, 2, and 3
Debt Instrument [Line Items]
Amortization period of payments of principal plus interest amounts	33 months
Interest rate	6.50%
Silicon Valley Bank \| Tranche 1, 2, and 3 \| Prime Rate
Debt Instrument [Line Items]
Interest rate, percentage point added to reference rate	1.00%
SVB and WestRiver
Debt Instrument [Line Items]
Total term loan borrowings				14,744,000
SVB and WestRiver \| Tranche 1
Debt Instrument [Line Items]
Number of warrants issued (in shares)	37,606				37,606
Exercise price of warrant (in usd per share)	$ 4.73				$ 4.73
Proceeds from lines of credit	$ 7,500,000
SVB and WestRiver \| Tranche 2
Debt Instrument [Line Items]
Number of warrants issued (in shares)	12,130				12,130
Exercise price of warrant (in usd per share)						$ 10.86
SVB and WestRiver \| Tranche 3
Debt Instrument [Line Items]
Number of warrants issued (in shares)	24,262				24,262
Exercise price of warrant (in usd per share)	$ 3.88				$ 3.88
Term Loan \| Silicon Valley Bank
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 7,500,000.0
Interest only period extended			Dec. 31, 2018
Amortization period of payments of principal plus interest amounts			24 months
Number of warrants issued (in shares)			49,713
Exercise price of warrant (in usd per share)			$ 9.659
Warrants exercisable date			Oct. 18, 2027
Percentage of aggregate principal amount			7.00%
Interest expense				400,000	$ 200,000
Term Loan \| Silicon Valley Bank \| Tranche A
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 3,500,000.0
Proceeds from lines of credit		$ 3,500,000
Term Loan \| Silicon Valley Bank \| Tranche B
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			2,000,000.0
Term Loan \| Silicon Valley Bank \| Tranche C
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 2,000,000.0
Term Loan \| Silicon Valley Bank \| Prepayment Made Prior To First Anniversary \| Loan and Security Agreement
Debt Instrument [Line Items]
Prepayment fee percentage			3.00%
Term Loan \| Silicon Valley Bank \| Prepayment Made By Period Second Anniversary [Member] \| Loan and Security Agreement
Debt Instrument [Line Items]
Prepayment fee percentage			2.00%
Term Loan \| Silicon Valley Bank \| Prepayment Made After Second Anniversary \| Loan and Security Agreement
Debt Instrument [Line Items]
Prepayment fee percentage			1.00%
Term Loan \| Silicon Valley Bank \| Tranche 2
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 2,500,000.0				2,500,000.0
Term Loan \| Silicon Valley Bank \| Tranche 3
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	5,000,000.0				5,000,000.0
Term Loan \| Silicon Valley Bank \| Tranche 1, 2, and 3
Debt Instrument [Line Items]
Debt discount				$ 400,000
Term Loan \| SVB and WestRiver
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	15,000,000.0				15,000,000.0
Term Loan \| SVB and WestRiver \| Tranche 1
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 7,500,000.0				$ 7,500,000.0