Retirement Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Employees' Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 400	$ 423	$ 1,202	$ 1,269
Expected Return on Plan Assets	(992)	(928)	(2,978)	(2,783)
Interest Cost (Benefit)		562
Interest Cost	582		1,743	1,682
Amortization of Prior Service Cost	47	32	142	98
Amortization of Net Loss (Gain)	0	0	0	0
Net Periodic Benefit Cost (Benefit)	37	89	109	266
Plan Contributions During the Period	0	0	0	0
Estimated Future Contributions in the Current Fiscal Year	0		0
Select Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	23	20	70	59
Expected Return on Plan Assets	0	237	0	237
Interest Cost (Benefit)		(157)
Interest Cost	76		224	3
Amortization of Prior Service Cost	9	9	29	29
Amortization of Net Loss (Gain)	0	6	0	18
Net Periodic Benefit Cost (Benefit)	108	115	323	346
Plan Contributions During the Period	100	127	348	382
Estimated Future Contributions in the Current Fiscal Year	116		116
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service Cost	7	11	23	34
Expected Return on Plan Assets	0	0	0	0
Interest Cost (Benefit)		79
Interest Cost	71		210	239
Amortization of Prior Service Cost	26	26	77	77
Amortization of Net Loss (Gain)	(128)	(84)	(383)	(253)
Net Periodic Benefit Cost (Benefit)	(24)	32	(73)	97
Plan Contributions During the Period	32	$ 31	123	$ 112
Estimated Future Contributions in the Current Fiscal Year	$ 41		$ 41