Fair Value Measurements Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Q3 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Other Restructuring Costs	$ 3.5
Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of Intangible Assets (Excluding Goodwill)		$ 6.2

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