Fair Value Measurements - Financial Assets (Liabilities) Carried at Fair Value (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Money market funds	$ 65.8	$ 168.0
Investment securities	0	28.8
Derivative assets	65.2	74.6
Derivative liabilities	(58.1)	(72.2)
Acquisition contingent consideration payable	(58.2)	(106.4)
Level 1 [Member]
Money market funds	65.8	168.0
Level 2 [Member]
Investment securities		28.8
Derivative assets	65.2	74.6
Derivative liabilities	(58.1)	(72.2)
Level 3 [Member]
Acquisition contingent consideration payable	$ (58.2)	$ (106.4)

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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