Commitments and Contingencies - Insurance Receivable Balance Sheet Roll Forward (Details) - Insurance recoveries - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]
Other receivable, beginning balance	$ 3,500	$ 0
Cash received	(10,927)	(8,486)
Other expenses	1,881	2,463
Business interruption	1,219	1,168
Other receivable, ending balance	1,547	3,500
Equipment
Insurance Recoveries Within Consolidated Condensed Financial Statements [Roll Forward]
Capital expenditures (equipment)	$ 5,874	$ 8,355

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

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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=120395209&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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