Goodwill (Schedule of Goodwill) (Details) $ in Thousands	6 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of the period	$ 411,346
Measurement period adjustment	(1,874)
Foreign currency translation	(1,900)
Goodwill, end of the period	407,572
Operating Segments \| Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period	224,370
Measurement period adjustment	(1,937)
Foreign currency translation	(1,463)
Goodwill, end of the period	220,970
Operating Segments \| Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period	186,976
Measurement period adjustment	63
Foreign currency translation	(437)
Goodwill, end of the period	$ 186,602

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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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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