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Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Feb. 15, 2017
Indefinite-lived intangible assets:
Goodwill	$ 95.7	$ 12.1	$ 7.2
Intangible Assets, Gross, (Including Goodwill)	758.0	708.0
Accumulated amortization:
Intangible Assets, Net (Excluding Goodwill)	433.7	408.1
Goodwill, Acquired During Period	80.1
Indefinite-lived Intangible Assets, Foreign Currency Translation Gain (Loss)	3.5
Business Combination-Related Identifiable Intangible [Member]
Accumulated amortization:
Accumulated Amortization	337.0	313.3
Net book value	421.0	394.7
Trademarks and Trade Names [Member]
Indefinite-lived intangible assets:
Trade names and trademarks	271.4	266.6
Software and Software Development Costs [Member]
Capitalized external-use software:
Capitalized Computer Software, Gross	30.2	27.6
Accumulated amortization	17.5	14.2
Net book value	12.7	13.4
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets:
Technology	116.6	82.6
Accumulated amortization:
Accumulated Amortization	76.4	72.9
Customer Relationships [Member]
Finite-lived intangible assets:
Customer relationships and other	370.0	358.8
Accumulated amortization:
Accumulated Amortization	$ 260.6	$ 240.4

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

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