Pension And Other Retirement Plans Net Periodic Benefit Cost For Pension Benefit Plan (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 203	$ 174	$ 416	$ 467
Interest cost	19,229	17,829	38,398	35,569
Expected return on plans’ assets	(23,769)	(24,823)	(47,554)	(49,641)
Recognized actuarial loss	0	8	0	8
Amortization of prior service costs	39	35	79	70
Net periodic benefit credit	$ (4,298)	$ (6,777)	$ (8,661)	$ (13,527)