Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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The cash inflow from a borrowing supported by a written promise to pay an obligation.

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Additional default interest rate.

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Debt financial maintenance covenant, minimum cash required.

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Interest rate floor.

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Prepayment penalty fee percentage.

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Notes Payable - Additional Information (Detail) - Loan and Security Agreement [Member] - USD ($)		1 Months Ended		3 Months Ended	6 Months Ended
	Jul. 29, 2020	Mar. 31, 2017	Oct. 31, 2016	Jun. 30, 2020	Jun. 30, 2020	Jul. 01, 2020
Debt Instrument [Line Items]
Effective Interest Rate On The Debt				17.80%	17.80%
Tranche One [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Sep. 01, 2020
LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate floor			0.50%
Horizon Technology Finance Corporation and Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Loan borrowed amount			$ 20,000,000
Debt instrument, interest rate floor			10.50%
Variable rate basis				one-month LIBOR
Interest rate description				Each loan tranche bears interest at a floating rate equal to 10.5% plus the amount by which the one-month London Interbank Offer Rate (“LIBOR”) exceeds 0.5%.
Prepayment penalty fee			2.00%
Minimum cash balance required in deposit account				$ 2,500,000	$ 2,500,000
Debt instrument covenant description					Beginning July 1, 2020, until the repayment of the full amounts due under the Loan Agreement, the Company must maintain a minimum cash balance equal to the lesser of (i) $1.0 million or (ii) the then-current aggregate outstanding principal balance of the loans.
Additional default interest rate					5.00%
Horizon Technology Finance Corporation and Silicon Valley Bank [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Minimum cash balance required in deposit account						$ 1,000,000
Horizon Technology Finance Corporation and Silicon Valley Bank [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Loan borrowed amount			$ 12,500,000
Debt instrument, payment terms					The Company borrowed the first tranche of $12.5 million upon close of the Loan Agreement in October 2016. The first tranche originally required only monthly interest payments until May 1, 2018 followed by equal monthly payments of principal plus accrued interest through the scheduled maturity date on May 1, 2020.
Debt instrument, final payment			$ 800,000
Debt instrument, maturity date			May 01, 2020
Debt instrument, frequency of periodic Payment					monthly
Horizon Technology Finance Corporation and Silicon Valley Bank [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Loan borrowed amount		$ 7,500,000
Debt instrument, payment terms					The Company borrowed the second tranche of $7.5 million in March 2017. The second tranche required only monthly interest payments until October 1, 2018 followed by equal monthly payments of principal plus accrued interest through the scheduled maturity date on October 1, 2020.
Debt instrument, final payment			$ 500,000
Debt instrument, maturity date			Oct. 01, 2020
Debt instrument, frequency of periodic Payment					monthly
Horizon Technology Finance Corporation and Silicon Valley Bank [Member] \| Tranche One And Two [Member]
Debt Instrument [Line Items]
Debt instrument, payment terms					The total amount of the payment was increased to $0.8 million as a result of the Second and Third Amendments. For each of the first and second tranches, the combined Second and Third Amendment require only monthly interest payments on the outstanding principal balance for the amounts due from April 1, 2020, through August 1, 2020
Debt instrument, final payment				$ 800,000	$ 800,000