Employee Benefits, Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		183 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024
Pension benefits qualified [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 7	$ 6	$ 22	$ 19
Interest cost	97	101	290	302
Expected return on plan assets	(118)	(126)	(354)	(378)
Amortization of net actuarial loss (gain)	35	35	104	105
Amortization of prior service cost (credit)	0	0	0	0
Net periodic benefit cost	21	16	62	48
Pension benefits nonqualified [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	0	0	0
Interest cost	5	5	13	14
Expected return on plan assets	0	0	0	0
Amortization of net actuarial loss (gain)	1	1	4	3
Amortization of prior service cost (credit)	0	0	0	0
Net periodic benefit cost	6	6	17	17
Other benefits [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	0	0	0
Interest cost	3	3	10	11
Expected return on plan assets	(6)	(5)	(19)	(18)
Amortization of net actuarial loss (gain)	(7)	(7)	(19)	(19)
Amortization of prior service cost (credit)	(2)	(2)	(7)	(7)
Net periodic benefit cost	$ (12)	$ (11)	$ (35)	$ (33)
Cash balance plan [Member]
Employee Benefits and Other Expenses Textual [Abstract]
New benefits accrued					$ 0