Segments - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Net sales	$ 647.2	$ 392.8	$ 1,775.5	$ 1,340.5
Segment Profit	246.3	176.1	716.0	622.9
Research and development expense	(9.5)	(5.2)	(23.7)	(15.9)
Amortization of intangible assets	(14.4)	(2.8)	(30.1)	(8.4)
Acquisition and integration costs		15.9
Gain on sale of real estate	0.0	4.6	0.0	4.6
Inventory step up	5.0	0.0	27.5	(26.5)
Other items, net	1.0	1.4	0.7	(0.8)
(Loss)/earnings before income taxes	9.4	31.5	25.4	168.3
Reclassification of research and development expense to acquisition and integration costs			0.3
Inventory step up			33.7	0.0
Acquisition foreign currency gains			0.9
Acquisition foreign currency contracts				9.9
Operating Segments
Segment Reporting Information [Line Items]
Segment Profit	144.8	93.0	440.6	355.1
Segment Reconciling Items
Segment Reporting Information [Line Items]
General corporate and other expenses	(29.9)	(24.7)	(78.3)	(71.0)
Global marketing expense	(3.0)	(4.6)	(12.5)	(13.0)
Research and development expense	(9.2)	(5.2)	(23.4)	(15.9)
Amortization of intangible assets	(14.4)	(2.8)	(30.1)	(8.4)
Acquisition and integration costs	28.0	15.9	159.9	41.0
Gain on sale of real estate	0.0	4.6	0.0	4.6
Interest and other financing items	(51.9)	(14.3)	(111.7)	(41.3)
Americas
Segment Reporting Information [Line Items]
Net sales	465.1	241.3	1,220.2	838.5
Americas \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	465.1	241.3	1,220.2	838.5
Segment Profit	103.8	60.4	308.6	239.2
International
Segment Reporting Information [Line Items]
Net sales	182.1	151.5	555.3	502.0
Acquisition foreign currency gains			(0.2)
International \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	182.1	151.5	555.3	502.0
Segment Profit	41.0	32.6	132.0	115.9
Selling, General and Administrative Expenses
Segment Reporting Information [Line Items]
Global marketing expense	(0.6)	(1.6)	(4.0)	(3.4)
Acquisition and integration costs	28.0		159.9	41.0
Selling, General and Administrative Expenses \| Segment Reconciling Items
Segment Reporting Information [Line Items]
Acquisition and integration costs	15.1	(22.4)	63.1	44.6
Advertising and Sales Promotion Expense
Segment Reporting Information [Line Items]
Global marketing expense	(2.4)	(3.0)	(8.5)	(9.6)
Cost of products sold
Segment Reporting Information [Line Items]
Acquisition and integration costs	12.4		44.1
Inventory step up	6.5		33.7
Interest Expense
Segment Reporting Information [Line Items]
Interest and other financing items		$ 3.4	65.6	$ 6.3
Research and Development Expense
Segment Reporting Information [Line Items]
Acquisition and integration costs			0.3
Acquisition-related Costs
Segment Reporting Information [Line Items]
Acquisition and integration costs	$ 0.2		$ 13.2

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Inventory Step Up Adjustment

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Reclassification of Research and Development Expense to Acquisition and Integration Costs

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to inventory acquired in connection with a business combination for which the initial accounting was incomplete.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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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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