Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025
Debt Instrument [Line Items]
Finance lease obligations	$ 85	$ 97
Total debt	2,886	10,612
Less — current maturities	(2,847)	(10,561)
Total long-term debt	39	51
Other
Debt Instrument [Line Items]
Long-term debt, gross	157	146
Revolving credit agreement \| Revolving credit agreement
Debt Instrument [Line Items]
Long-term debt, gross	386	7,969
Secured Debt \| Revolving credit agreement
Debt Instrument [Line Items]
Long-term debt, gross	2,258	2,400
Unamortized debt issuance costs	$ 42	$ 50

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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