Assets Held for Sale, Discontinued Operations and Disposals - Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Reversal of allowance for doubtful accounts, net	$ 5	$ (59)
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		(665)
Depreciation and amortization		135
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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