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Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Millions | Sep. 30, 2017 | Feb. 15, 2017 | Sep. 30, 2016
--- | --- | --- | ---
Indefinite-lived intangible assets: |  |  |
Goodwill | $ 12.9 | $ 7.2 | $ 5.4
Intangible Assets, Gross (Excluding Goodwill) | 715.6 |  | 696.3
Accumulated amortization: |  |  |
Accumulated Amortization | 293.4 |  | 273.7
Intangible Assets, Net (Including Goodwill) | 439.3 |  | 434.6
Business Combination-Related Identifiable Intangible [Member] |  |  |
Accumulated amortization: |  |  |
Net book value | 422.2 |  | 422.6
Trademarks and Trade Names [Member] |  |  |
Indefinite-lived intangible assets: |  |  |
Trade names and trademarks | 266.8 |  | 263.6
Software and Software Development Costs [Member] |  |  |
Capitalized external-use software: |  |  |
Capitalized Computer Software, Gross | 28.4 |  | 20.9
Accumulated amortization | 11.3 |  | 8.9
Net book value | 17.1 |  | 12.0
Technology-Based Intangible Assets [Member] |  |  |
Finite-lived intangible assets: |  |  |
Technology | 76.7 |  | 76.8
Accumulated amortization: |  |  |
Accumulated Amortization | 72.2 |  | 71.5
Customer Relationships [Member] |  |  |
Finite-lived intangible assets: |  |  |
Customer relationships and other | 359.2 |  | 350.5
Accumulated amortization: |  |  |
Accumulated Amortization | $ 221.2 |  | $ 202.2

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