Segments - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 848.6	$ 736.8
Segment Profit	337.9	301.3
Research and development expense	7.6	8.9
Amortization of intangible assets	(15.5)	(13.8)
Loss on extinguishment of debt	(5.7)	(4.2)
Other items, net	(0.7)	0.9
Loss / (earnings) before income taxes	87.3	58.7
Acquisition foreign currency gains	11.0
Acquisition and integration costs	18.3	19.3
Operating Segments
Segment Reporting Information [Line Items]
Segment Profit	215.7	181.4
Segment Reconciling Items
Segment Reporting Information [Line Items]
General corporate and other expenses	(24.0)	(24.9)
Global marketing expense	(9.4)	(6.1)
Research and development expense	7.5	8.5
Amortization of intangible assets	(15.5)	(13.8)
Acquisition and integration costs	18.3	19.3
Interest and other financing items	(47.3)	(46.8)
Americas
Segment Reporting Information [Line Items]
Net sales	586.6	514.5
Americas | Operating Segments
Segment Reporting Information [Line Items]
Net sales	586.6	514.5
Segment Profit	155.9	129.2
International
Segment Reporting Information [Line Items]
Net sales	262.0	222.3
Acquisition foreign currency gains	10.9
International | Operating Segments
Segment Reporting Information [Line Items]
Net sales	262.0	222.3
Segment Profit	59.8	52.2
Selling, general and administrate expense
Segment Reporting Information [Line Items]
Global marketing expense	(4.9)	(2.9)
Acquisition and integration costs	10.4	11.1
Advertising and Sales Promotion Expense
Segment Reporting Information [Line Items]
Global marketing expense	(4.5)	(3.2)
Research and Development Expense
Segment Reporting Information [Line Items]
Acquisition and integration costs	0.1
Acquisition and integration costs	$ 0.1	$ 0.4