Supplemental Information (Other Noncurrent Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016
Supplemental Information [Abstract]
Derivative instruments	$ 133.9	$ 204.4
Other long-term receivables	82.1	16.9
Prepaid tax	5.1	37.0
Deferred tax assets	174.5	185.0
Pension benefits	18.4	0.0
Deposits	34.8	36.5
Other	193.0	191.2
Other noncurrent assets	$ 641.8	$ 671.0

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting and classified as noncurrent.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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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, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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