Commitments and Contingencies - Insurance Receivable Balance Sheet Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]
Business interruption	$ 546
Insurance recoveries
Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]
Other receivable, beginning balance	1,547	$ 3,500
Cash received	(4,548)	(10,927)
Other expenses	58	1,881
Business interruption	546	1,219
Other receivable, ending balance	0	1,547
Equipment \| Insurance recoveries
Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]
Capital expenditures (equipment)	$ 2,397	$ 5,874

Business Interruption Losses, Offset By Proceeds

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- Definition

Insurance Recoveries, Used For Property Damage Incurred

+ References

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- Definition

Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]

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- Definition

Payment For Business Interruption Insurance

+ References

No definition available.

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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- Definition

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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