Discontinued Operations - Unconsolidated Subsidiaries - Statements of Operations (Details) - ULVAC Cryogenics, Inc. - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Total revenue	$ 22,756	$ 23,106	$ 45,050	$ 45,979
Gross profit	8,305	8,879	17,241	18,112
Operating Income	4,078	4,690	9,214	10,046
Net income	$ 2,602	$ 2,738	$ 6,108	$ 7,052

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

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