Pension Plan and Retirement Benefits - Defined Benefit Plans - Expense (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2007	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Pension Plan and Retirement Benefits
Accrued pension and postretirement benefits		$ 57,637	$ 77,521
Defined Benefit Pension Plan
Pension Plan and Retirement Benefits
Pension plan expense		(66)	(1,921)	$ 4,713
Accrued pension and postretirement benefits		4,819	12,954
Contribution to plan		6,000	6,000
Projected benefit obligation		224,790	231,275	315,466
Pension Plans Defined Benefit Us [Member]
Pension Plan and Retirement Benefits
Contribution to plan		6,000	6,000	21,000
Pension Plans Defined Benefit Non Us [Member]
Pension Plan and Retirement Benefits
Contribution to plan		0	0	0
Non Qualified Pension Plans Defined Benefit [Member]
Pension Plan and Retirement Benefits
Pension plan expense		57	3	37
Accrued pension and postretirement benefits		492	530
Defined Benefit Other Postretirement Benefit Plan
Pension Plan and Retirement Benefits
Pension plan expense		2,309	3,819	3,387
Accrued pension and postretirement benefits		52,326	64,037
Maximum liability related to total retiree health care costs under plan amendment	$ 5,000
Contribution to plan		2,128	2,643
Projected benefit obligation		52,326	$ 64,037	$ 82,964
UNITED STATES
Pension Plan and Retirement Benefits
Projected benefit obligation		217,393
Pension Plans Defined Benefit Non US
Pension Plan and Retirement Benefits
Projected benefit obligation		$ 7,397