Discontinued Operations - Non-cash Items and Capital Expenditures (Details) - Discontinued Operations, Held-for-sale - Semiconductor Cryogenics Business - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Discontinued Operation, Alternative Cash Flow Information [Abstract]
Depreciation and amortization		$ 196		$ 391
Capital expenditures	$ 99	46	$ 407	72
Stock-based compensation	129	246	420	492
Earnings of equity method investment	$ (1,269)	$ (1,422)	$ (3,041)	$ (3,602)

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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