Asset acquisition contingency period ending year.

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- Definition

Contingent obligation due and payable as a result of achievement of regulatory milestone(s).

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Asset acquisition contingent payments upon achievement of regulatory milestones.

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Asset acquisition installment payment, beginning period.

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Asset acquisition installment payment, ending period.

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Commitments and contingencies.

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Gross amount of contractual obligation, including the portion of the obligation satisfied to date.

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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The cash outflows from the purchase of net carrying value allocated to in-process research and development costs and materials acquired in a business combination.

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The amount of purchased research and development assets that are acquired in a business combination have no alternative future use and are therefore written off in the period of acquisition.

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Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended				24 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2024
Commitments And Contingencies [Line Items]
Payments to acquire in-process research and development			$ 750,000
Acquisition charge for in-process of research and development			890,000
Other long-term liabilities	$ 11,649,000	$ 8,020,000
Other accrued liabilities current	407,000	278,000
Embolitech LLC [Member]
Commitments And Contingencies [Line Items]
Contingent payments upon achievement of regulatory milestones	$ 1,000,000.0
Installment payment beginning period	2022
Installment payment ending period	2024
CRO [Member]
Commitments And Contingencies [Line Items]
Contractual obligation remaining to be paid	$ 7,000,000
CRO [Member] \| Minimum [Member]
Commitments And Contingencies [Line Items]
Gross contractual obligation	37,000,000
CRO [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Gross contractual obligation	40,000,000
CRO [Member] \| Maximum [Member] \| CRO Pass-through Expenses [Member]
Commitments And Contingencies [Line Items]
Gross contractual obligation	29,000,000
In-Process Research and Development [Member] \| Embolitech LLC [Member]
Commitments And Contingencies [Line Items]
Payments to acquire in-process research and development	$ 1,000,000.0	1,000,000.0		$ 5,000,000.0
Contingency period ending year	2033
Contingent obligation due and payable as a result of achievement of regulatory milestone(s)	$ 1,000,000.0
Other long-term liabilities	6,400,000	2,200,000
Other accrued liabilities current		$ 1,100,000
In-Process Research and Development [Member] \| Embolitech LLC [Member] \| Forecast [Member]
Commitments And Contingencies [Line Items]
Contractual obligation payable in fiscal 2022 through fiscal 2024					$ 2,500,000
In-Process Research and Development [Member] \| Medical Device [Member]
Commitments And Contingencies [Line Items]
Payments to acquire in-process research and development	$ 200,000		800,000
Contingent payments upon achievement of regulatory milestones			1,100,000
Contingency period ending year	2022
Acquisition charge for in-process of research and development			$ 900,000