Retirement Benefits (Schedule of Allocation of Plan Assets, Fair Value Hierarchy) (Details) - Defined Benefit Pension Plan [Member] - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 206,145	$ 202,060	$ 291,107
United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	155,370	154,481	221,263
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50,775	47,579	$ 69,844
Level 1 [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	155,370	154,481
Level 1 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149	467
Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50,626	47,112
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,534	2,732
Cash and Cash Equivalents | Level 1 [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,385	2,265
Cash and Cash Equivalents | Level 1 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149	467
Debt Security, Corporate, US
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	103,401	106,653
Debt Security, Corporate, US | Level 1 [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	103,401	106,653
Domestic Equity Large Cap Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31,136	28,088
Domestic Equity Large Cap Fund | Level 1 [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31,136	28,088
International Equity Large Cap Growth Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18,448	17,475
International Equity Large Cap Growth Fund | Level 1 [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18,448	17,475
Private Equity Funds Foreign Japan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,830	1,775
Private Equity Funds Foreign Japan | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,830	1,775
Private Equity Funds Pooled Funds Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,600	1,610
Private Equity Funds Pooled Funds Foreign | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,600	1,610
Fixed Income Funds Japan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,785	3,875
Fixed Income Funds Japan | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,785	3,875
Fixed Income Funds Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,287	1,325
Fixed Income Funds Foreign | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,287	1,325
Global Target Return Equity Bond Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,719	11,533
Global Target Return Equity Bond Fund | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,719	11,533
United Kingdom Index Linked Equity Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,253
United Kingdom Index Linked Equity Fund | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,253
Index linked international equity fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4,271
Index linked international equity fund | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4,271
Corporate Debt Securities United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,319	12,124
Corporate Debt Securities United Kingdom | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,319	12,124
Pooled funds: Index linked U.K. government securities fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,601	3,701
Pooled funds: Index linked U.K. government securities fund [Member] | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,601	3,701
Pooled funds: Index linked U.K. long-term government securities fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,485	4,645
Pooled funds: Index linked U.K. long-term government securities fund [Member] | Level 2 [Member] | Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 4,485	$ 4,645