Goodwill (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 797,853	$ 813,250
Impairment loss, Goodwill	8,640
Effects of Foreign Currency Translation	19,039	(15,397)
Goodwill, Ending Balance	808,252	797,853
Aerospace [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	455,423	455,423
Goodwill, Ending Balance	455,423	455,423
Industrial [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	342,430	357,827
Impairment loss, Goodwill	8,640
Effects of Foreign Currency Translation	19,039	(15,397)
Goodwill, Ending Balance	$ 352,829	$ 342,430

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.

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