Leases - Supplemental cash flow information (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 268	$ 330
Operating cash flows from short-term leases	17	21
Operating cash flows from finance leases	1	1
Financing cash flows from finance leases	0	2
Cash received from subleases	$ (7)	$ (10)

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- Definition

Amount of interest paid on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-URI https://asc.fasb.org//1943274/2147478964/842-20-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-URI https://asc.fasb.org//1943274/2147478964/842-20-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 45
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-URI https://asc.fasb.org//1943274/2147479041/842-20-45-5

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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-URI https://asc.fasb.org//1943274/2147479041/842-20-45-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

Amount of cash inflow from lease payment, classified as operating activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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- Definition

Amount of cash outflow for short-term lease payment excluded from lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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