Goodwill And Intangible Assets (Changes In The Carrying Amount Of Goodwill By Reporting Segment) (Details) $ in Millions	6 Months Ended
	Mar. 31, 2019 USD ($)
Goodwill [Line Items]
As of September 30, 2018	$ 1,454.7
Foreign currency impact	(5.4)
As of March 31, 2019	1,449.3
Hardware & Home Improvement [Member]
Goodwill [Line Items]
As of September 30, 2018	704.3
Foreign currency impact	(2.6)
As of March 31, 2019	701.7
Global Pet Supplies [Member]
Goodwill [Line Items]
As of September 30, 2018	435.9
Foreign currency impact	(2.9)
As of March 31, 2019	433.0
Home and Garden [Member]
Goodwill [Line Items]
As of September 30, 2018	196.5
Foreign currency impact
As of March 31, 2019	196.5
Home And Personal Care [Member]
Goodwill [Line Items]
As of September 30, 2018	118.0
Foreign currency impact	0.1
As of March 31, 2019	$ 118.1