Acquisitions (Schedule of Recognized Identified Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019	Jan. 28, 2019	Jan. 02, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Goodwill	$ 1,016.0	$ 1,004.8			$ 244.2
Battery Acquisition
Business Acquisition [Line Items]
Cash and cash equivalents				$ 37.8
Trade receivables				54.2
Inventories				80.8
Other current assets				28.2
Assets held for sale				794.6
Property, plant and equipment, net				133.2
Goodwill				496.0
Other intangible assets, net				805.8
Other assets				10.3
Current portion of capital leases				(1.2)
Accounts payable				(39.2)
Other current liabilities				(19.3)
Long-term debt				(14.7)
Liabilities held for sale				(394.6)
Other liabilities				(9.5)
Net assets acquired				$ 1,962.4
Spectrum Auto Care Acquisition
Business Acquisition [Line Items]
Cash and cash equivalents			$ 3.3
Trade receivables			39.7
Inventories			98.6
Other current assets			8.9
Property, plant and equipment, net			70.8
Goodwill			274.0
Other intangible assets, net			965.3
Deferred tax assets			4.2
Other assets			1.7
Current portion of capital leases			(0.4)
Accounts payable			(28.6)
Other current liabilities			(10.9)
Long-term debt			(31.9)
Other liabilities (deferred tax liabilities)			(211.9)
Net assets acquired			$ 1,182.8