Goodwill (Schedule) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Goodwill [Roll Forward]
Goodwill, beginning of the period	$ 392,890	$ 411,346
Business combinations and divestitures	(2,318)	(1,738)
Measurement period adjustments	298	(1,874)
Goodwill reclassified to assets held for sale		(14,911)
Foreign currency translation	1,699	(3,409)
Goodwill, end of the period	397,205	392,890
Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period		224,370
Business combinations and divestitures		0
Measurement period adjustments		(1,937)
Goodwill reclassified to assets held for sale		0
Foreign currency translation		(420)
Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period		186,976
Business combinations and divestitures		(1,738)
Measurement period adjustments		63
Goodwill reclassified to assets held for sale		(14,911)
Foreign currency translation		(2,989)
Operating Segments [Member] \| Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period	222,013
Business combinations and divestitures	(2,723)
Measurement period adjustments	0
Foreign currency translation	(355)
Goodwill, end of the period	224,381	222,013
Operating Segments [Member] \| Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period	170,877
Business combinations and divestitures	(405)
Measurement period adjustments	298
Foreign currency translation	2,054
Goodwill, end of the period	$ 172,824	$ 170,877

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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