Employee Benefits - Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pension Benefits
Net Periodic Benefit Cost
Net Periodic Other Benefit Costs	$ 137	$ 179	$ 412	$ 427
Pension Benefits | United States
Net Periodic Benefit Cost
Service cost	90	86	268	257
Interest cost	116	112	348	336
Expected return on plan assets	(149)	(140)	(447)	(419)
Amortization of prior service costs (credits)	1	1	3	3
Amortization of actuarial losses (gains)	60	51	182	152
Settlement losses	0	53	0	53
Net Periodic Other Benefit Costs	118	163	354	382
Pension Benefits | International
Net Periodic Benefit Cost
Service cost	14	15	41	44
Interest cost	48	49	143	145
Expected return on plan assets	(51)	(52)	(148)	(154)
Amortization of prior service costs (credits)	3	2	8	6
Amortization of actuarial losses (gains)	5	2	14	6
Acquisitions / (divestitures)	0	0	0	(2)
Net Periodic Other Benefit Costs	19	16	58	45
Other Benefits
Net Periodic Benefit Cost
Service cost	8	9	25	25
Interest cost	24	23	74	72
Amortization of prior service costs (credits)	(7)	(6)	(19)	(19)
Amortization of actuarial losses (gains)	(4)	(5)	(11)	(14)
Net Periodic Other Benefit Costs	$ 21	$ 21	$ 69	$ 64