Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Indefinite-lived intangible assets:
Goodwill	$ 5.4	$ 5.4
Intangible Assets, Gross (Excluding Goodwill)	785.5	785.5
Accumulated amortization:
Accumulated Amortization	311.5	289.1
Intangible Assets, Net (Including Goodwill)	486.0	507.3
Business Combination-Related Identifiable Intangible [Member]
Accumulated amortization:
Net book value	474.0	496.4
Trademarks and Trade Names [Member]
Indefinite-lived intangible assets:
Trade names and trademarks	299.6	299.6
Software and Software Development Costs [Member]
Capitalized external-use software:
Capitalized Computer Software, Gross	20.9	17.9
Accumulated amortization	8.9	7.0
Net book value	12.0	10.9
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets:
Technology	80.3	80.3
Accumulated amortization:
Accumulated Amortization	75.0	74.2
Customer Relationships [Member]
Finite-lived intangible assets:
Customer relationships and other	400.2	400.2
Accumulated amortization:
Accumulated Amortization	$ 236.5	$ 214.9

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