Pension and Other Postretirement Employee Benefits (Components Of Net Periodic Cost (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,849	$ 2,045
Interest cost	2,812	2,633
Expected return on plan assets	(3,145)	(3,382)
Amortization of prior service cost (credit)	18	21
Amortization of actuarial loss (gain)	1,954	3,578
Net periodic cost before pension settlement charge	3,488	4,895
Pension settlement charge	14,165
Total net periodic cost	17,653	4,895
OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	79	168
Interest cost	229	317
Amortization of prior service cost (credit)	156	(298)
Amortization of actuarial loss (gain)	(95)	545
Net periodic cost before pension settlement charge	369	732
Total net periodic cost	$ 369	$ 732