Assets Held for Sale, Discontinued Operations and Disposals - Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2020	Mar. 31, 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	$ (32)	$ 1,141
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)	(9,267)
Depreciation and amortization	180	287
(Reversal of) provision for allowance for doubtful accounts, net	(66)	981
Purchases of property, plant and equipment	$ 1	$ 96

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

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