Leases - Components of lease costs (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Operating Lease:
Total lease costs	$ 140	$ 174	$ 281	$ 346
Total lease costs, net of sublease interest income	139	173	280	344
Interest expense
Finance Lease:
Interest on lease liabilities	0	1	0	1
Selling, general and administrative
Operating Lease:
Operating lease cost	132	162	264	324
Short-term lease cost	8	11	17	21
Revenue.
Operating Lease:
Less sublease interest income	$ (1)	$ (1)	$ (1)	$ (2)

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract before netting of sublease income.

+ References

No definition available.

+ Details

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

- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-4

+ Details

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

+ Details

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

+ Details

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- Details

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- Details

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- Details

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