Benefit Plans (Schedule Of Components Of Net Periodic Benefit Cost (Income)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 15	$ 17
Interest cost	52	46
Expected return on plan assets	(123)	(131)
Amortization:
Net loss	24	33
Prior service cost (credit)	2	1
Net periodic benefit (income) cost	(30)	(34)
Postretirement [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	5	5
Interest cost	10	11
Expected return on plan assets	(3)	(4)
Amortization:
Net loss	4	7
Prior service cost (credit)	(12)	(6)
Net periodic benefit (income) cost	$ 4	$ 13