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Organization Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring	$ 0.5	$ 2.6	$ 0.5	$ 2.6	$ 3.1	$ 2.8
Restructuring and other charges	$ 0.6	$ 3.9	3.6	6.1
Payments			(3.0)	(2.2)
Mueller One Project [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			$ 0.4	$ 2.0