Discontinued Operations - Non-cash Items and Capital Expenditures (Details) - Discontinued Operations, Held-for-sale - Semiconductor Cryogenics Business - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Discontinued Operation, Alternative Cash Flow Information [Abstract]
Depreciation and amortization	$ 4	$ 743	$ 919
Capital expenditures	666	302	1,049
Stock-based compensation	635	966	705
Earnings of equity method investment	$ (6,188)	$ (6,788)	$ (9,834)

Discontinued Operation Earnings Losses of Equity Method Investments

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Stock Based Compensation Discontinued Operations

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

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