Business Segment Information - Schedule of Sales and Property by Geographic Region (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Sales and property by geographic region
Sales	$ 1,570.0	$ 1,394.0	$ 1,681.3	$ 1,684.5	$ 1,730.2	$ 1,665.1	$ 1,657.2	$ 1,642.3	$ 6,329.8	$ 6,694.8	$ 6,666.0
Property	574.4				571.9				574.4	571.9	576.8
North America
Sales and property by geographic region
Sales									3,760.2	4,014.3	3,964.1
Property	429.4				443.8				429.4	443.8	450.2
Europe, Middle East and Africa
Sales and property by geographic region
Sales									1,249.3	1,249.8	1,286.8
Property	81.9				60.5				81.9	60.5	53.3
Asia Pacific
Sales and property by geographic region
Sales									868.7	908.6	933.3
Property	42.8				41.9				42.8	41.9	42.9
Latin America
Sales and property by geographic region
Sales									451.6	522.1	481.8
Property	$ 20.3				$ 25.7				$ 20.3	$ 25.7	$ 30.4