Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Debt Instrument [Line Items]
Finance lease obligations	$ 13	$ 22
Total debt	20,706	21,165
Less – current maturities	(17,148)	(18,496)
Total long-term debt	3,558	2,669
Unamortized debt issuance costs	(29)	(32)
Other, net of unamortized debt issuance costs $(29) and $(32), respectively
Debt Instrument [Line Items]
Long-term debt, gross	5,526	5,581
Revolving credit agreement \| Revolving credit agreement
Debt Instrument [Line Items]
Long-term debt, gross	9,301	8,930
Foreign subsidiary borrowings
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,866	$ 6,632

Amount of short-term and long-term debt and lease obligation.

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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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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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