Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Plans [Member]
Components of net periodic benefit cost:
Service cost	$ 28	$ 38
Interest cost	30	21
Expected return on plan assets	(50)	(48)
Amortization of:
Net actuarial (gain) loss	(2)	13
Prior service credit	(5)	(4)
Net periodic benefit cost	1	20
Other Postretirement Benefit Plans [Member]
Components of net periodic benefit cost:
Service cost	1	2
Interest cost	3	2
Expected return on plan assets	0	0
Amortization of:
Net actuarial (gain) loss	(1)	0
Prior service credit	(1)	(1)
Net periodic benefit cost	$ 2	$ 3