Benefit Plans (Schedule Of Components Of Net Periodic Benefit Cost (Income)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	$ 16	$ 29	$ 48
Interest cost	84	51	250	155
Expected return on plan assets	(121)	(123)	(364)	(370)
Amortization:
Net loss (gain)	1	24	3	72
Prior service cost (credit)	1	2	4	5
Net periodic benefit cost (income)	(26)	(30)	(78)	(90)
Postretirement [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	7	11	17
Interest cost	15	11	49	31
Expected return on plan assets	(1)	(4)	(5)	(10)
Amortization:
Net loss (gain)	(2)	6	(2)	14
Prior service cost (credit)	(10)	(11)	(30)	(34)
Net periodic benefit cost (income)	$ 5	$ 9	$ 23	$ 18