Retirement Benefits (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Components of Net Periodic Benefit Cost
Net periodic benefit cost (benefit)			$ (895)	$ (818)
Defined contribution plan, employer contributions	$ 108	$ 99	429	476
Pension Benefits
Components of Net Periodic Benefit Cost
Service cost	92	104	276	311
Interest cost	285	263	853	790
Expected return on plan assets	(661)	(627)	(1,982)	(1,884)
Amortization of prior service credit	0	(3)	0	(7)
Net periodic benefit cost (benefit)	(284)	(263)	(853)	(790)
Defined benefit plan, contributions by Employer	26	26	77	79
OPB
Components of Net Periodic Benefit Cost
Service cost	2	4	6	12
Interest cost	12	13	36	40
Expected return on plan assets	(28)	(26)	(83)	(79)
Amortization of prior service credit	0	0	(1)	(1)
Net periodic benefit cost (benefit)	(14)	(9)	(42)	(28)
Defined benefit plan, contributions by Employer	$ 9	$ 8	$ 29	$ 29