Employee Pension Plans (Summary Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Summary of net periodic benefit cost
Interest cost	$ 758	$ 948	$ 1,516	$ 1,896
Expected return on plan assets	(1,006)	(1,043)	(2,012)	(2,086)
Amortization of net loss	592	463	1,184	926
Other	231	225	462	450
Net periodic benefit cost	$ 575	$ 593	$ 1,150	$ 1,186