Pension and Other Postretirement Employee Benefits (Components Of Net Periodic Cost (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,356	$ 1,849
Interest cost	3,138	2,812
Expected return on plan assets	(3,028)	(3,145)
Amortization of prior service cost	11	18
Amortization of actuarial (gain) loss	(21)	1,954
Net periodic cost before pension settlement charge	1,456	3,488
Pension settlement charge	0	14,165
Total net periodic cost	1,456	17,653
OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	27	79
Interest cost	294	229
Expected return on plan assets	0	0
Amortization of prior service cost	0	156
Amortization of actuarial (gain) loss	(166)	(95)
Net periodic cost before pension settlement charge	155	369
Pension settlement charge	0	0
Total net periodic cost	$ 155	$ 369