Long-Term Debt - Components of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Debt Disclosure [Abstract]
Industrial development revenue bonds	$ 0	$ 400
Less: current portion	0	(400)
Total long-term debt	$ 0	$ 0

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant