Discontinued Operations - Non-cash Items and Capital Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Discontinued Operations, Held-for-sale \| Semiconductor Automation Business
Discontinued Operation, Alternative Cash Flow Information [Abstract]
Depreciation and amortization	$ 8,472	$ 11,374	$ 13,153
Capital expenditures	6,414	4,815	2,341
Stock-based compensation	$ 7,405	$ 5,501	6,412
Discontinued Operations, Disposed of by Sale \| Semiconductor Cryogenics Business
Discontinued Operation, Alternative Cash Flow Information [Abstract]
Depreciation and amortization			4
Capital expenditures			666
Stock-based compensation			635
Earnings of equity method investment			$ (6,188)

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Stock Based Compensation Discontinued Operations

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Amount of capital expenditure attributable to discontinued operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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-Section 50
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Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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