Goodwill Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
Jun. 30, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of the period	$ 321,913
Business combinations and divestitures	6,074
Measurement period adjustment	(637)
Foreign currency translation	(3,078)
Goodwill, end of the period	324,272
Operating Segments [Member] \| Industrial [Member]
Goodwill [Roll Forward]
Goodwill, beginning of the period	128,190
Business combinations and divestitures	2,462
Measurement period adjustment	(323)
Foreign currency translation	(2,972)
Goodwill, end of the period	127,357
Operating Segments [Member] \| Municipal [Member]
Goodwill [Roll Forward]
Goodwill, beginning of the period	9,865
Business combinations and divestitures	(145)
Measurement period adjustment	0
Foreign currency translation	21
Goodwill, end of the period	9,741
Operating Segments [Member] \| Product [Member]
Goodwill [Roll Forward]
Goodwill, beginning of the period	183,858
Business combinations and divestitures	3,757
Measurement period adjustment	(314)
Foreign currency translation	(127)
Goodwill, end of the period	$ 187,174

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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.

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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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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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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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