Assets Held for Sale, Discontinued Operations and Disposals - Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Reversal of allowance for doubtful accounts, net	$ 28	$ (32)
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)
Depreciation and amortization		180
Reversal of allowance for doubtful accounts, net		(66)
Purchases of property, plant and equipment		$ 1

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

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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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