Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2020	Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative asset, fair value, gross liability	$ 10.6
Redeemable noncontrolling interest, fair value	1,661.9	$ 0.0
Other liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative asset, fair value, gross liability	10.6
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative asset, fair value, gross liability	0.0
Redeemable noncontrolling interest, fair value	1,661.9
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative asset, fair value, gross liability	10.6
Redeemable noncontrolling interest, fair value	0.0
Debt, fair value	$ 625.8

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value of liability associated with 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.

+ References

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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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