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, 2023	Dec. 31, 2022
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial loss (gain)	$ 2,560	$ 1,717
Amortization of actuarial loss	(51)	(543)
Amortization of prior service credit	(58)	(58)
Settlements	(1,815)	0
Total recognized in other comprehensive loss	636	1,116
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial loss (gain)	173	(44)
Amortization of actuarial loss	(44)	(64)
Amortization of prior service credit	50	52
Total recognized in other comprehensive loss	$ 179	$ (56)