Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Annual compound growth rate after 5 years assumption used to calculate the terminal value of the forecasted cash flows for the annual goodwill impairment test.

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Weighted average cost of capital assumption used to discount forecasted cash flows for the annual goodwill impairment test

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Goodwill (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Goodwill (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Goodwill [Line Items]
Goodwill addition		$ 257,447
Impairment		0
Assumed annual compound growth rate after five or ten years	3.32%
Aerospace [Member]
Goodwill [Line Items]
Goodwill addition			$ 0
Industrial [Member]
Goodwill [Line Items]
Goodwill addition		$ 257,447	$ 0
Minimum [Member]
Goodwill [Line Items]
Weighted average cost of capital assumption	9.83%
Maximum [Member]
Goodwill [Line Items]
Weighted average cost of capital assumption	12.76%