Goodwill (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 813,250	$ 556,545
Additions		257,447
Effects of Foreign Currency Translation	(15,397)	(742)
Goodwill, Ending Balance	797,853	813,250
Aerospace [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	455,423	455,423
Additions
Effects of Foreign Currency Translation
Goodwill, Ending Balance	455,423	455,423
Industrial [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	357,827	101,122
Additions		257,447
Effects of Foreign Currency Translation	(15,397)	(742)
Goodwill, Ending Balance	$ 342,430	$ 357,827

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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