Product Warranties (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Product Warranty Liability [Line Items]
Product Warranty Accrual, Current	$ 6,115	$ 4,922
Product warranties	1,724	2,332
Other Current Liabilities [Member]
Product Warranty Liability [Line Items]
Product Warranty Accrual, Current	6,115	4,922	$ 8,907	$ 11,164
Warranty provision for sales	4,738	5,745	4,930
Settlement of warranty claims	(4,890)	(6,529)	(6,836)
Foreign currency translation and other	550	63	(351)
Standard and Extended Product Warranty Accrual, Sale of Business	795	3,264
Amounts related to sale of the Memcor product line			0
Other Noncurrent Liabilities [Member]
Product Warranty Liability [Line Items]
Product warranties	1,724	2,332	3,360	$ 6,110
Warranty provision for sales	701	1,915	654
Settlement of warranty claims	(1,170)	(999)	(3,132)
Foreign currency translation and other	(274)	(350)	(272)
Standard and Extended Product Warranty Accrual, Sale of Business	$ 135	$ 1,594
Amounts related to sale of the Memcor product line			$ 0

Disposal Group, Including Discontinued Operation, Product Warranty, Current

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Standard and Extended Product Warranty Accrual, Sale of Business

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.

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