Pension and Other Postretirement Employee Benefits (Components Of Net Periodic Cost (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,355	$ 1,652	$ 4,066	$ 5,153
Interest cost	3,139	2,611	9,414	8,034
Expected return on plan assets	(3,028)	(2,259)	(9,081)	(7,662)
Amortization of prior service cost	10	19	32	55
Amortization of actuarial (gain) loss	(21)	1,150	(63)	4,252
Net periodic cost before pension settlement charge			4,368	9,832
Pension settlement charge			0	14,165
Total net periodic cost	1,455	3,173	4,368	23,997
OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	27	79	82	237
Interest cost	294	228	881	686
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	0	155	0	467
Amortization of actuarial (gain) loss	(166)	(96)	(498)	(286)
Net periodic cost before pension settlement charge			465	1,104
Pension settlement charge			0	0
Total net periodic cost	$ 155	$ 366	$ 465	$ 1,104