Benefit Obligations (Schedule of Net Periodic Benefit Costs Recognized) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 4
Interest cost	17	13
Expected return on plan assets	(41)	(51)
Total	(21)	(34)
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	0
Expected return on plan assets	0	0
Total	$ 0	$ 0