Discontinued Operations - Unconsolidated Subsidiaries - Statements of Operations (Details) - ULVAC Cryogenics, Inc. - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Total revenue	$ 22,299	$ 22,878
Gross profit	8,928	9,226
Operating Income	5,124	5,343
Net income	$ 3,496	$ 4,285

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

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Amount of income (loss) from continuing operations reported by an equity method investee.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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