Retirement Plans (Components Of Net Periodic Pension Benefit (Income) Cost) (Details) - United Kingdom Subsidiary [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 2,362	$ 2,451	$ 4,738	$ 4,827
Expected return on plan assets	(3,213)	(2,878)	(6,445)	(5,669)
Amortization of unrecognized loss	648	658	1,301	1,297
Net periodic pension (income) cost	$ (203)	$ 231	$ (406)	$ 455

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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