Commitments And Contingencies [Line Items]

No definition available.

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- Definition

Effective period of lease agreement.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Lease expiration period.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Expense associated with licensing agreements with third parties.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of leases.

+ References

No definition available.

+ Details

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Net cash outflow or inflow from monetary allowance granted by the landlord to a tenant to entice tenant to move into landlords building which will enable the tenant to prepare the leased premises for tenants occupancy.

+ References

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Sep. 30, 2019 USD ($) Lease	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Commitments And Contingencies [Line Items]
Number of leases \| Lease	2
Restricted cash	$ 608	$ 608
Rent expense	$ 2,492	2,033	$ 2,025
License Agreement Terms [Member]
Commitments And Contingencies [Line Items]
License agreement, recorded liability paid			$ 115
First Lease [Member] \| 500 Arsenal Street, Watertown, Massachusetts [Member]
Commitments And Contingencies [Line Items]
Office lease expiration period	Sep. 30, 2022
Tenant improvement allowance	$ 598
Outstanding letter of credit	608	608
Restricted cash	$ 608	$ 608
Second Lease [Member] \| 400 Talcott Avenue, Watertown, Massachusetts [Member]
Commitments And Contingencies [Line Items]
Period of lease agreement	2018-09
Office lease expiration period	2024-08