Employee Benefits - Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pension Benefits
Net Periodic Benefit Cost
Net Periodic Other Benefit Costs	$ 137	$ 123
Pension Benefits | United States
Net Periodic Benefit Cost
Service cost	89	86
Interest cost	116	112
Expected return on plan assets	(149)	(140)
Amortization of prior service costs (credits)	1	1
Amortization of actuarial losses (gains)	61	51
Settlement losses	0	0
Net Periodic Other Benefit Costs	118	110
Pension Benefits | International
Net Periodic Benefit Cost
Service cost	14	15
Interest cost	47	47
Expected return on plan assets	(50)	(51)
Amortization of prior service costs (credits)	3	2
Amortization of actuarial losses (gains)	5	2
Settlement losses	0	0
Acquisitions / (divestitures)	0	(2)
Net Periodic Other Benefit Costs	19	13
Other Benefits
Net Periodic Benefit Cost
Service cost	8	8
Interest cost	25	24
Amortization of prior service costs (credits)	(6)	(6)
Amortization of actuarial losses (gains)	(4)	(5)
Net Periodic Other Benefit Costs	$ 23	$ 21