Restructuring Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	$ 11.2	$ 7.4	$ 21.8	$ 13.7
2019 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs	21.0		21.0
Restructuring Costs	5.8	7.4	12.4	13.7
2020 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	5.4	0.0	9.4	0.0
Minimum | 2020 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs	6.0		6.0
Americas
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	11.2	6.9	20.4	12.8
International
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	$ 0.0	$ 0.5	$ 1.4	$ 0.9