Pension And Other Retirement Plans Net Periodic Benefit Cost For Pension Benefit Plan (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 213	$ 293
Interest cost	19,169	17,740
Expected return on plans’ assets	(23,785)	(24,818)
Amortization of prior service costs	40	35
Net periodic benefit credit	$ (4,363)	$ (6,750)