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Share-Based Payments - PEP, RSU (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022
Information concerning outstanding and exercisable options |  |  |
Compensation expense related to share-based payments | $ 61.5 | $ 45.9 | $ 38.5
Unrecognized compensation expense | $ 68.7 | $ 48.3 |
Recognition period of unrecognized compensation expense | 3 years | 3 years |
Performance Earnings Program | PEP Units |  |  |
Information concerning outstanding and exercisable options |  |  |
Vesting period | 3 years |  |

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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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