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Restructuring Charges (Details) $ in Thousands	12 Months Ended
Restructuring Charges (Details) $ in Thousands	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($) Rate	Sep. 30, 2022 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 8,655	$ 65,388	$ 7,909
Q1 2024 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 9,800
Q3 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance Costs		$ 53,200
Number of employees affected		620
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent \| Rate		9.00%
Other Restructuring Costs		$ 3,500
Restructuring charges		56,700
Payments for Restructuring		49,700
Restructuring Reserve		3,500
Q1 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 8,700
Q1 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 7,900