Retirement Benefits (Schedule of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,161	$ 1,125
Interest cost	1,572	1,719
Expected return on plan assets	(4,138)	(3,919)
Amortization of: Net actuarial loss	363	619
Amortization of: Prior service cost (benefit)	248	240
Net periodic retirement pension (benefit) cost	(794)	(216)
Contributions paid	543	1,131
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		1
Interest cost	150	195
Amortization of: Net actuarial loss	7	12
Amortization of: Prior service cost (benefit)		1
Net periodic retirement pension (benefit) cost	157	209
Contributions paid - other postretirement plans	38	345
United States [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	432	415
Interest cost	1,239	1,398
Expected return on plan assets	(3,536)	(3,087)
Amortization of: Net actuarial loss	135	358
Amortization of: Prior service cost (benefit)	242	234
Net periodic retirement pension (benefit) cost	(1,488)	(682)
Other Countries [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	729	710
Interest cost	333	321
Expected return on plan assets	(602)	(832)
Amortization of: Net actuarial loss	228	261
Amortization of: Prior service cost (benefit)	6	6
Net periodic retirement pension (benefit) cost	694	466
Contributions paid	$ 543	$ 1,131