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Retirement Benefit Plans (Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Loss (Income)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial gain	$ 1,717	$ (3,793)
Amortization of actuarial loss	(543)	(718)
Amortization of prior service credit	(58)	(59)
Total recognized in other comprehensive loss (income)	1,116	(4,570)
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial gain	(44)	(48)
Amortization of actuarial loss	(64)	(19)
Amortization of prior service credit	52	54
Transfers	0	126
Total recognized in other comprehensive loss (income)	$ (56)	$ 113

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