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Restructuring Charges (Details) $ in Thousands	12 Months Ended
Restructuring Charges (Details) $ in Thousands	Sep. 30, 2023 USD ($) Rate	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 65,388	$ 7,909	$ 0
Q3 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 56,700
Number of employees affected	620
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent \| Rate	9.00%
Severance Costs	$ 53,200
Other Restructuring Costs	3,500
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