Components Of Net Periodic Pension Cost (Income) (Details) - United Kingdom Subsidiary - UK Plan - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 9,722	$ 5,693	$ 5,326
Expected return on plan assets	(11,417)	(12,088)	(12,726)
Amortization of unrecognized loss	2,611	2,073	3,642
Net periodic pension cost (income)	$ 916	$ (4,322)	$ (3,758)

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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