Retirement Benefits (Schedule of Amounts Recognized in Balance Sheet and Accumulated Other Comprehensive (Earnings) Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Defined Benefit Pension Plan [Member]
Amounts recognized in statement of financial position consist of:
Other non-current assets	$ 43,339	$ 34,051
Accrued liabilities	(1,084)	(976)
Other non-current liabilities	(30,595)	(28,936)
Net over/(under) funded status at end of year	11,660	4,139
Amounts recognized in accumulated other comprehensive (earnings) losses consist of:
Unrecognized net prior service cost (benefit)	3,264	3,937
Unrecognized net losses (gains)	680	9,363
Total amounts recognized	3,944	13,300	$ 19,083
Deferred taxes	(5,293)	(8,498)
Amounts recognized in accumulated other comprehensive (earnings)	(1,349)	4,802
Other Postretirement Benefit Plans [Member]
Amounts recognized in statement of financial position consist of:
Accrued liabilities	(1,739)	(1,803)
Other non-current liabilities	(13,597)	(14,994)
Net over/(under) funded status at end of year	(15,336)	(16,797)
Amounts recognized in accumulated other comprehensive (earnings) losses consist of:
Unrecognized net losses (gains)	(6,412)	(6,225)
Total amounts recognized	(6,412)	(6,225)	(2,815)
Deferred taxes	1,292	1,247
Amounts recognized in accumulated other comprehensive (earnings)	(5,120)	(4,978)
United States [Member] | Defined Benefit Pension Plan [Member]
Amounts recognized in statement of financial position consist of:
Other non-current assets	29,172	24,159
Other non-current liabilities	(1,024)	(2,122)
Net over/(under) funded status at end of year	28,148	22,037
Amounts recognized in accumulated other comprehensive (earnings) losses consist of:
Unrecognized net prior service cost (benefit)	2,777	3,475
Unrecognized net losses (gains)	8,527	14,822
Total amounts recognized	11,304	18,297	(6,361)
Deferred taxes	(6,101)	(7,801)
Amounts recognized in accumulated other comprehensive (earnings)	5,203	10,496
Foreign Plan | Defined Benefit Pension Plan [Member]
Amounts recognized in statement of financial position consist of:
Other non-current assets	14,167	9,892
Accrued liabilities	(1,084)	(976)
Other non-current liabilities	(29,571)	(26,814)
Net over/(under) funded status at end of year	(16,488)	(17,898)
Amounts recognized in accumulated other comprehensive (earnings) losses consist of:
Unrecognized net prior service cost (benefit)	487	462
Unrecognized net losses (gains)	(7,847)	(5,459)
Total amounts recognized	(7,360)	(4,997)	$ 25,444
Deferred taxes	808	(697)
Amounts recognized in accumulated other comprehensive (earnings)	$ (6,552)	$ (5,694)