Revenue Recognition (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Sales	$ 2,916.2	$ 2,930.2	$ 5,847.7	$ 5,927.6
Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 2,916.2	$ 2,930.2	$ 5,847.7	$ 5,927.6
Percent sales by supply mode	100.00%	100.00%	100.00%	100.00%
Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 1,287.2	$ 1,245.8	$ 2,574.8	$ 2,497.9
Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	774.1	779.7	1,591.2	1,573.5
Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	727.4	667.9	1,424.6	1,399.1
Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	32.8	35.7	65.6	71.1
Corporate and other | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	94.7	201.1	191.5	386.0
On-site | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 1,552.5	$ 1,404.4	$ 3,040.8	$ 2,898.4
Percent sales by supply mode	53.00%	48.00%	52.00%	48.00%
On-site | Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 760.5	$ 695.5	$ 1,473.6	$ 1,409.6
On-site | Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	523.1	495.9	1,052.4	999.1
On-site | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	249.2	194.5	477.5	453.7
On-site | Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	19.7	18.5	37.3	36.0
On-site | Corporate and other | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0	0.0	0.0
Merchant | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 1,269.0	$ 1,324.7	$ 2,615.4	$ 2,643.2
Percent sales by supply mode	44.00%	45.00%	45.00%	45.00%
Merchant | Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 526.7	$ 550.3	$ 1,101.2	$ 1,088.3
Merchant | Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	251.0	283.8	538.8	574.4
Merchant | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	478.2	473.4	947.1	945.4
Merchant | Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	13.1	17.2	28.3	35.1
Merchant | Corporate and other | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0	0.0	0.0
Sale of Equipment | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 94.7	$ 201.1	$ 191.5	$ 386.0
Percent sales by supply mode	3.00%	7.00%	3.00%	7.00%
Sale of Equipment | Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Sale of Equipment | Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0	0.0	0.0
Sale of Equipment | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0	0.0	0.0
Sale of Equipment | Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0	0.0	0.0
Sale of Equipment | Corporate and other | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 94.7	$ 201.1	$ 191.5	$ 386.0
Financing And Lease Arrangment | Revenue Benchmark | Revenue Source Concentration Risk
Disaggregation of Revenue [Line Items]
Interest income associated with financing and lease arrangements as a percentage of total consolidated sales			1.00%