Pension Plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Weighted average interest crediting rate used in only cash balance pension plan		4.10%
Defined benefit plan, plan assets, increase (decrease) for actual return (loss)		$ 2,300	$ 7,400	$ (3,000)
Defined benefit plan, plan assets, contributions by employer		$ 3,000	$ 3,000	$ 2,600
Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, vesting period		1 year
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, vesting period		5 years
Forecast
Defined Benefit Plan Disclosure [Line Items]
Net periodic pension income	$ 400
Defined benefit plan, plan assets, contributions by employer	3,100
Defined benefit plan, plan assets, contributions by employer, directly to plans	$ 600
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine net periodic pension cost for fiscal years ended September 30, Rate of return on plan assets		5.00%	5.00%	5.40%
Net periodic pension income		$ (807)	$ 2,310	$ 1,924
Defined benefit plan, plan assets, increase (decrease) for actual return (loss)		2,348	7,383
Defined benefit plan, plan assets, contributions by employer		$ 3,007	$ 3,049
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.70%	1.00%	1.10%
Pension Plan | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate			1.00%
Pension Plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.70%
Pension Plan | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Current asset allocation target for fixed income securities		100.00%