Revenue Recognition (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Sales	$ 2,930.2	$ 3,200.1	$ 5,927.6	$ 6,374.8
Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 2,930.2	$ 3,200.1	$ 5,927.6	$ 6,374.8
Percent sales by supply mode	100.00%	100.00%	100.00%	100.00%
Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 1,245.8	$ 1,373.1	$ 2,497.9	$ 2,757.3
Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	779.7	813.9	1,573.5	1,591.7
Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	667.9	752.9	1,399.1	1,544.8
Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	35.7	44.8	71.1	86.2
Corporate and other | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	201.1	215.4	386.0	394.8
On-site | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 1,404.4	$ 1,574.4	$ 2,898.4	$ 3,224.8
Percent sales by supply mode	48.00%	49.00%	48.00%	51.00%
On-site | Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 695.5	$ 801.9	$ 1,409.6	$ 1,647.7
On-site | Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	495.9	490.3	999.1	948.0
On-site | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	194.5	259.4	453.7	587.5
On-site | Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	18.5	22.8	36.0	41.6
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	$ 1,324.7	$ 1,410.3	$ 2,643.2	$ 2,755.2
Percent sales by supply mode	45.00%	44.00%	45.00%	43.00%
Merchant | Americas | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	$ 550.3	$ 571.2	$ 1,088.3	$ 1,109.6
Merchant | Asia | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	283.8	323.6	574.4	643.7
Merchant | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	473.4	493.5	945.4	957.3
Merchant | Middle East and India | Operating Segments
Disaggregation of Revenue [Line Items]
Sales	17.2	22.0	35.1	44.6
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	$ 201.1	$ 215.4	$ 386.0	$ 394.8
Percent sales by supply mode	7.00%	7.00%	7.00%	6.00%
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	$ 201.1	$ 215.4	$ 386.0	$ 394.8