Business Segment Information (Reconciliation of Operating Income) (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended	12 Months Ended
May 01, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Segment Reporting Information [Line Items]
Operating income		$ 539.2	$ 569.7		$ 1,677.4	$ 1,541.2
Facility closure		0.0	0.0	$ (29.0)	0.0	(29.0)
Cost reduction actions		0.0	(25.5)		0.0	(25.5)	$ (25.5)
Gain on exchange of equity affiliate investments	$ 29.1	0.0	29.1		0.0	29.1
Company headquarters relocation income (expense)		0.0	0.0		33.8	0.0
Segment Total
Segment Reporting Information [Line Items]
Operating income		539.2	566.1		1,643.6	1,566.6
Segment Reconciling Items
Segment Reporting Information [Line Items]
Facility closure		0.0	0.0		0.0	(29.0)
Cost reduction actions		0.0	(25.5)		0.0	(25.5)
Gain on exchange of equity affiliate investments		0.0	29.1		0.0	29.1
Company headquarters relocation income (expense)		$ 0.0	$ 0.0		$ 33.8	$ 0.0

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

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The net result for the period of deducting operating expenses from operating revenues.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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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.

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