Assets Held for Sale, Discontinued Operations and Disposals - Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Reversal of) provision for allowance for doubtful accounts, net	$ (26)	$ 1,104
(Loss) gain on sale of subsidiary	(13,708)	1,614
Tempress and SoLayTec \| Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations, net of tax	(11,816)	(8,113)
Depreciation and amortization	180	426
(Reversal of) provision for allowance for doubtful accounts, net	(66)	887
(Loss) gain on sale of subsidiary	(10,916)	1,614
Purchases of property, plant and equipment	$ 1	$ 118

Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of cash outflow from the acquisition of or improvements to long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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