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2023 Restructuring Plan - Accrual Activity and Payments Relating to Cash-Based Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Restructuring Cost and Reserve [Line Items]
Costs	$ 12,672	$ 0	$ 12,672	$ 0
2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Costs	9,052
Payments	(6,274)
Restructuring reserve	2,778		2,778
Severance and related benefit costs \| 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Costs	8,622
Payments	(5,844)
Restructuring reserve	2,778		2,778
Other associated costs \| 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Costs	430
Payments	(430)
Restructuring reserve	$ 0		$ 0