Goodwill and Other Intangible Assets - Changes in Carrying amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Goodwill
Beginning balance	$ 1,071.1	$ 1,075.5
Acquisition of businesses	551.9	14.6
Translation	27.3	(19.0)
Ending balance	1,650.3	1,071.1
Architecture & Software
Goodwill
Beginning balance	432.3	422.3
Acquisition of businesses	161.2	14.6
Translation	15.9	(4.6)
Ending balance	609.4	432.3
Control Products & Solutions
Goodwill
Beginning balance	638.8	653.2
Acquisition of businesses	390.7	0.0
Translation	11.4	(14.4)
Ending balance	$ 1,040.9	$ 638.8

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: 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=120320667&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.

+ References

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