Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Pension Plans [Member]
Components of Net Periodic Benefit Cost:
Service cost	$ 28	$ 27	$ 82	$ 81
Interest cost	32	34	97	102
Expected return on plan assets	(57)	(56)	(172)	(167)
Amortization of:
Net actuarial gain	(2)	(2)	(6)	(6)
Prior service cost	1	1	4	4
Settlement loss	0	3	1	6
Net periodic benefit cost	2	7	6	20
Other Postretirement Benefit Plans [Member]
Components of Net Periodic Benefit Cost:
Service cost	0	0	2	2
Interest cost	3	3	8	9
Expected return on plan assets	0	0	0	0
Amortization of:
Net actuarial gain	(2)	(2)	(5)	(6)
Prior service cost	0	1	0	1
Settlement loss	0	0	0	0
Net periodic benefit cost	$ 1	$ 2	$ 5	$ 6