Employee Benefits and Expenses, Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		159 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022
Employee Benefits and Other Expenses Textual [Abstract]
Net periodic benefit cost, expected long-term rate of return on plan assets	5.34%
Net periodic benefit cost, discount rate	4.48%
Qualified Plan [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 5	$ 4	$ 15	$ 13
Interest cost	95	77	244	219
Expected return on plan assets	(119)	(150)	(384)	(456)
Amortization of net actuarial loss (gain)	34	31	100	106
Amortization of prior service credit	0	0	0	0
Settlement loss	48	35	157	97
Net periodic benefit cost	63	(3)	132	(21)
Nonqualified Plan [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	0	0	0
Interest cost	3	3	8	9
Expected return on plan assets	0	0	0	0
Amortization of net actuarial loss (gain)	3	4	9	11
Amortization of prior service credit	0	0	0	0
Settlement loss	0	0	1	2
Net periodic benefit cost	6	7	18	22
Other benefits [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	0	0	0
Interest cost	1	2	6	8
Expected return on plan assets	(5)	(5)	(16)	(14)
Amortization of net actuarial loss (gain)	(6)	(5)	(17)	(15)
Amortization of prior service credit	(2)	(2)	(7)	(7)
Settlement loss	0	0	0	0
Net periodic benefit cost	(12)	(10)	(34)	(28)
Cash balance plan [Member]
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost					$ 0
Cash balance plan [Member] | Qualified Plan [Member]
Components of net periodic benefit cost [Abstract]
Settlement loss	$ 48	$ 35	$ 151	$ 97
Employee Benefits and Other Expenses Textual [Abstract]
Discount rate	5.44%	2.80%	5.44%	2.80%	5.44%
(Increase) decrease for remeasurement due to settlement	$ 143	$ 224	$ 253	$ (123)
Settlement	$ 95	$ 189	$ 102	$ (220)