Discontinued Operations - Non-cash Items and Capital Expenditures (Details) - Discontinued Operations, Held-for-sale - Semiconductor Cryogenics Business - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Discontinued Operation, Alternative Cash Flow Information [Abstract]
Depreciation and amortization	$ 4	$ 196	$ 4	$ 588
Capital expenditures	87	55	494	127
Stock-based compensation	215	238	635	730
Earnings of equity method investment	$ (1,835)	$ (1,329)	$ (4,876)	$ (4,931)

Discontinued Operation Earnings Losses of Equity Method Investments

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Stock Based Compensation Discontinued Operations

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Amount of capital expenditure attributable to 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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