Income Taxes - Income Before Taxes (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Income Tax Disclosure [Abstract]
United States									$ 71.0	$ 29.3	$ 58.9
Foreign									252.6	223.9	217.1
Income Before Taxes	$ 86.7	$ 83.7	$ 77.5	$ 75.7	$ 58.5	$ 69.1	$ 58.3	$ 67.3	$ 323.6	$ 253.2	$ 276.0

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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