Employee Benefits - Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pension Benefits
Net Periodic Benefit Cost
Net Periodic Other Benefit Costs	$ 125	$ 114	$ 248	$ 304
Pension Benefits | United States
Net Periodic Benefit Cost
Service cost	85	117	171	235
Interest cost	112	69	224	135
Expected return on plan assets	(139)	(162)	(279)	(323)
Amortization of prior service costs (credits)	1	1	2	1
Amortization of actuarial losses (gains)	50	60	101	125
Settlement losses	0	21	0	107
Net Periodic Other Benefit Costs	109	106	219	280
Pension Benefits | International
Net Periodic Benefit Cost
Service cost	14	21	29	43
Interest cost	49	35	96	71
Expected return on plan assets	(51)	(44)	(102)	(92)
Amortization of prior service costs (credits)	2	1	4	3
Amortization of actuarial losses (gains)	2	4	4	8
Settlement losses	0	(9)	0	(9)
Acquisitions / (divestitures)	0	0	(2)	0
Net Periodic Other Benefit Costs	16	8	29	24
Other Benefits
Net Periodic Benefit Cost
Service cost	8	10	16	21
Interest cost	25	16	49	31
Amortization of prior service costs (credits)	(7)	(7)	(13)	(13)
Amortization of actuarial losses (gains)	(4)	3	(9)	6
Net Periodic Other Benefit Costs	$ 22	$ 22	$ 43	$ 45