Acquisitions (Narrative) (Details) - USD ($) $ in Millions						1 Months Ended	3 Months Ended								9 Months Ended	12 Months Ended
	Jan. 01, 2019	Nov. 15, 2018	Jul. 06, 2018	Jul. 02, 2018	Jan. 15, 2018	Jun. 30, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016	Jan. 31, 2018
Business Acquisition [Line Items]
Cash																$ 38.1	$ 0.0	$ 344.0
Integration Related Costs							$ 30.4	$ 13.0	$ 14.1	$ 4.1	$ (0.5)	$ 3.1	$ 1.1	$ 0.5
Interest expense																98.4	53.1	54.3
Pre-tax gain in Other items, net																15.2	0.0	0.0
Interest income on restricted cash																5.2	0.0	0.0
Acquisition withholding tax							0.0	$ 0.5	$ 5.5	$ 0.0
Foreign currency contracts | Not Designated as Hedging Instrument
Business Acquisition [Line Items]
Pre-tax gain in Other items, net																9.3	(1.4)
Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Integration Related Costs																	$ 4.0	$ 10.0
Nu Finish Acquisition
Business Acquisition [Line Items]
Consideration transferred				$ 38.1
Revenue																2.3
Earnings before income taxes																0.2
Inventory adjustment							$ 0.2
Other identifiable intangible assets				$ 21.8
Spectrum Brands Holdings
Business Acquisition [Line Items]
Cash					$ 2,000.0
Borrowings					100.0
Transaction costs					$ 11.0														$ 2.0
Acquisition and integration costs																84.6
Interest expense																41.9
Interest income on restricted cash																5.2
Acquisition withholding tax																6.0
Spectrum Brands Holdings | Foreign currency contracts | Not Designated as Hedging Instrument
Business Acquisition [Line Items]
Pre-tax gain in Other items, net						$ 9.4									$ 15.2
Amount escrowed			$ 5.8
Spectrum Brands Holdings | Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Integration Related Costs																$ 62.9
Spectrum Brands Holdings | Scenario, Forecast | Minimum
Business Acquisition [Line Items]
Expected net purchase price	$ 1,400.0
Spectrum Brands Holdings | Scenario, Forecast | Maximum
Business Acquisition [Line Items]
Expected net purchase price	$ 1,500.0
Spectrum Auto Care Acquisition | Subsequent Event
Business Acquisition [Line Items]
Consideration transferred		$ 1,250.0
Cash		938.0
Newly-issued equity for acquisition		312.0
Additional equity or equity linked capital to replace a portion of committed financing		500.0
Spectrum Auto Care Acquisition | Subsequent Event | Revolving Facility
Business Acquisition [Line Items]
Committed financing		$ 1,100.0