Long-term Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Long-term obligations (less current portion)
Finance lease obligations	$ 7,118	$ 7,384
Environmental post-closure monitoring and maintenance activities	355	407
Long-term disability	189	210
Deferred dividends	198	199
Less amounts due within one year	(412)	(352)
Long-term obligations (less current portion)	$ 7,448	$ 7,848
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]	Long-term obligations (less current portion)	Long-term obligations (less current portion)

Represents the amount of accrued deferred dividends.

No definition available.

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- Definition

Represents the current portion accrued as of the balance sheet date of both the total costs for environmental loss contingencies and the present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

No definition available.

+ Details

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- Definition

Represents the noncurrent portion accrued as of the balance sheet date of both the total costs for environmental loss contingencies and the present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

No definition available.

+ Details

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- Definition

Present value of minimum lease payments for finance leases included in capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

No definition available.

+ Details

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- Definition

The amount of Long-term disability.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-10

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-7

+ Details

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- Definition

Indicates line item in statement of financial position that includes accrual for environmental loss contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481899/410-30-55-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480102/450-20-S99-1

+ Details

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