Retirement Plans (Components Of Net Periodic Pension Benefit Cost (Income)) (Details) - United Kingdom Subsidiary [Member] - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 2,376	$ 2,376
Expected return on plan assets	(3,232)	(2,791)
Amortization of unrecognized loss	653	639
Net periodic pension (income) cost	$ (203)	$ 224

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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