Fair Value Measurements (Schedule of Recurring Fair Value Measurements) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	$ 85.1	$ 83.4
Total Liabilities at Fair Value	127.8	121.5
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	0.0	0.0
Total Liabilities at Fair Value	0.0	0.0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	85.1	83.4
Total Liabilities at Fair Value	127.8	121.5
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	0.0	0.0
Total Liabilities at Fair Value	0.0	0.0
Forward exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	47.4	49.3
Derivative liabilities	71.8	88.8
Forward exchange contracts | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0.0	0.0
Derivative liabilities	0.0	0.0
Forward exchange contracts | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	47.4	49.3
Derivative liabilities	71.8	88.8
Forward exchange contracts | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0.0	0.0
Derivative liabilities	0.0	0.0
Interest Rate Management Contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	37.7	34.1
Derivative liabilities	56.0	32.7
Interest Rate Management Contracts | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0.0	0.0
Derivative liabilities	0.0	0.0
Interest Rate Management Contracts | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	37.7	34.1
Derivative liabilities	56.0	32.7
Interest Rate Management Contracts | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0.0	0.0
Derivative liabilities	$ 0.0	$ 0.0