Notes Payable - Additional Information (Detail) - USD ($)		12 Months Ended
Oct. 29, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Interest expense		$ 502,000
Loan and Security Agreement [Member]
Debt Instrument [Line Items]
Interest expense		502,000
Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility, interest rate	9.65%
Credit facility, payment terms	The Company will make interest only payments through December 1, 2021. The interest only period may be extended to June 1, 2022 upon satisfaction of certain milestones. Following the interest only period, the Company will repay the principal balance and interest of the advances in equal monthly installments through November 1, 2023.
Percentage of prepayment amount during first year	3.00%
Percentage of prepayment amount during second year	2.00%
Percentage of prepayment amount during third year	1.00%
Prepayment or repayment percentage	4.85%
Additional advance prepayment or repayment percentage	4.85%
Carrying value of debt		$ 24,648,000
Loan and Security Agreement [Member] \| Term Loan Facility [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Debt instrument, variable rate	4.40%
Hercules Capital, Inc. [Member] \| Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility, aggregate principal amount	$ 50,000,000
First Tranche [Member] \| Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Prepayment or repayment charge	1,213,000
Carrying value of debt	24,575,000
First Tranche [Member] \| Hercules Capital, Inc. [Member] \| Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Gross proceeds from debt	25,000,000
Second Tranche Available Through March 15, 2021 [Member] \| Hercules Capital, Inc. [Member] \| Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility, aggregate principal amount	12,500,000
Third Tranche Available Upon Approval on or Prior to June 30, 2021 [Member] \| Hercules Capital, Inc. [Member] \| Loan and Security Agreement [Member] \| Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility, aggregate principal amount	$ 12,500,000

Debt instrument additional advance prepayments percentage.

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Debt Instrument prepayment charges.

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Debt instruments prepayment percentage.

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Percentage of prepayment amount during first year following closing date.

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Percentage of prepayment amount during second year following closing date.

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Percentage of prepayment amount during third year following closing date.

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- Definition

Proceeds from issuance of long term debt gross.

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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Description of the frequency of the required periodic payments of interest, principal, or both, and the amount, if set, or a description of a formula upon which payment is based.

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The effective interest rate during the reporting period.

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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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