Retirement Plans (Components Of Net Periodic Pension Benefit Cost (Income)) (Details) - United Kingdom Subsidiary [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 2,472	$ 1,344	$ 7,299	$ 4,325
Expected return on plan assets	(2,903)	(2,856)	(8,572)	(9,182)
Amortization of unrecognized loss	664	490	1,961	1,574
Net periodic pension cost (income)	$ 233	$ (1,022)	$ 688	$ (3,283)