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

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

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Face (par) amount of debt instrument at time of issuance.

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

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Amount of the fees associated with providing collateral for the credit facility.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Long-term debt - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2018	Sep. 30, 2017	Nov. 30, 2020	Oct. 31, 2020	Sep. 30, 2020
Exercise Price Of Warrants				$ 21.24	$ 14.85
Debt instrument description of interest rate			interest rate of prime plus 3.0%
Line of credit facility maintenance fees	$ 100
Revolving Credit Facility \| SVB
Proceeds from long term line of credit			$ 10,000
Line of credit facility non current portion outstanding	$ 0					$ 0
Long term debt instrument effective rate of interest at a point in time	11.60%
Floating Interest Rate \| Revolving Credit Facility \| SVB
Debt instrument variable interest rate spread			1.00%
Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt instrument principal amount			$ 20,000
Debt instrument term			51 months
Debt Instrument, Fee Amount			$ 700
Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt instrument principal amount			$ 10,000
Warrants To Purchase Common Stock			64,127
Exercise Price Of Warrants			$ 6.24
Proceeds from long term debt			$ 10,000
Tranche Two \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt instrument principal amount			5,000
Debt Instrument Maturity		Jan. 31, 2018
Tranche Three \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt instrument principal amount			5,000
Debt Instrument Maturity		Jun. 30, 2018
Prior Loan Refinance \| Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Proceeds from long term debt			7,800
New Advance \| Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Proceeds from long term debt			$ 2,200