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Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Feb. 15, 2017
Indefinite-lived intangible assets:
Goodwill	$ 12.1	$ 12.9	$ 7.2
Intangible Assets, Gross (Excluding Goodwill)	720.1	715.6
Accumulated amortization:
Accumulated Amortization	313.3	293.4
Intangible Assets, Net (Including Goodwill)	420.2	439.3
Business Combination-Related Identifiable Intangible [Member]
Accumulated amortization:
Net book value	406.8	422.2
Trademarks and Trade Names [Member]
Indefinite-lived intangible assets:
Trade names and trademarks	266.6	266.8
Software and Software Development Costs [Member]
Capitalized external-use software:
Capitalized Computer Software, Gross	27.6	28.4
Accumulated amortization	14.2	11.3
Net book value	13.4	17.1
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets:
Technology	82.6	76.7
Accumulated amortization:
Accumulated Amortization	72.9	72.2
Customer Relationships [Member]
Finite-lived intangible assets:
Customer relationships and other	358.8	359.2
Accumulated amortization:
Accumulated Amortization	$ 240.4	$ 221.2

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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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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a projected indefinite period of benefit.

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