Note 2 - Commitments - Supplement Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Operating lease costs	$ 1,370	$ 1,493
Variable operating lease costs	23	(254)
Total operating lease cost	1,393	1,239
Amortization of right-of-use assets	69	121
Interest on lease liabilities	4	10
Total finance lease cost	$ 73	$ 131

Amount of lease cost recognized by finance lease contract.

No definition available.

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Period Type:	duration

- Definition

Amount of variable lease cost (credit), excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

+ Details

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

+ Details

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

- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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-Publisher FASB
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+ 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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

+ Details

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