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

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The carrying value as of the balance sheet date of the current and noncurrent portions 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 ($)	1 Months Ended		12 Months Ended
	Dec. 31, 2021	Sep. 30, 2017	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Repayments of long-term debt			$ 1,558,000	$ 3,333,000	$ 3,333,000
Revolving Credit Facility \| SVB
Debt Instrument [Line Items]
Proceeds from long term line of credit		$ 10,000,000
Outstanding loan balance			$ 0
Floating Interest Rate \| Revolving Credit Facility \| SVB
Debt Instrument [Line Items]
Debt instrument variable interest rate spread		1.00%
Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Debt instrument principal amount		$ 20,000,000
Debt instrument term		51 months
Final payment fee		$ 700,000
Fourth Amended and Restated Loan and Security Agreement \| Prime Rate \| SVB
Debt Instrument [Line Items]
Debt instrument variable interest rate spread		3.00%
Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Debt instrument principal amount		$ 10,000,000
Repayments of long-term debt	$ 10,000,000
Warrants to purchase common stock (in shares)		64,127
Exercise price of warrants (in dollars per share)		$ 6.24
Proceeds from long term debt		$ 10,000,000
Tranche Two \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Debt instrument principal amount		5,000,000
Tranche Three \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Debt instrument principal amount		5,000,000
Prior Loan Refinance \| Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Proceeds from long term debt		7,800,000
New Advance \| Tranche One \| Fourth Amended and Restated Loan and Security Agreement \| SVB
Debt Instrument [Line Items]
Proceeds from long term debt		$ 2,200,000