Goodwill (Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 556,545	$ 555,684
Additions	257,447
Effects of Currency Translation	(742)	861
Goodwill, Ending Balance	813,250	556,545
Aerospace [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	455,423	455,423
Additions		0
Effects of Currency Translation	0	0
Goodwill, Ending Balance	455,423	455,423
Industrial [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	101,122	100,261
Additions	257,447	0
Effects of Currency Translation	(742)	861
Goodwill, Ending Balance	357,827	$ 101,122
Business Acquisition, Acquiree - L'Orange [Member]
Goodwill [Line Items]
Additions	257,447
Goodwill, Ending Balance	257,447
Business Acquisition, Acquiree - L'Orange [Member] \| Industrial [Member]
Goodwill [Line Items]
Additions	$ 257,447

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
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

+ References

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