Discontinued Operations - Unconsolidated Subsidiaries - Statements of Operations (Details) - ULVAC Cryogenics, Inc. - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Total revenue	$ 88,357	$ 94,652	$ 104,667
Gross profit	35,127	34,982	41,241
Operating Income	17,791	18,405	26,340
Net income	$ 12,483	$ 13,345	$ 19,451

The amount of gross profit (loss) reported by an equity method investment of the entity.

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