Assets Held for Sale, Discontinued Operations and Disposals - Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Reversal of allowance for doubtful accounts, net	$ (59)	$ 44
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)	(2,620)
Depreciation and amortization	135	146
Reversal of allowance for doubtful accounts, net	(66)	(46)
Purchases of property, plant and equipment	$ 1	$ 98

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

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