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Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to defined contribution savings plans		$ 199	$ 175	$ 158
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 19,100	$ 17,200
Percentage of Company's pension investments categorized as level 3 assets		4.00%	4.00%
Pension Benefits | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 788	$ 765
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,045	947	$ 1,292
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		65
Other Postretirement Benefits | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 0	$ 0
United States
Defined Benefit Plan Disclosure [Line Items]
Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests		11.00%
Expected rate of return on plan assets		7.00%	6.70%	6.70%
United States | Forecast | Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	7.75%
United States | U.S. equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		25.00%
United States | U.S. equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		40.00%
United States | International equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		10.00%
United States | International equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		20.00%
United States | Fixed Income Investments | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		35.00%
United States | Fixed Income Investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		45.00%
United States | Cash And Other Investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		8.00%
United States | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 10,300	$ 9,700
Fair value of plan assets		9,804	9,094	$ 13,067
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		260
United States | Pension Benefits | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	4	6
International | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		9,562	$ 8,473	$ 12,195
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		$ 190
Expected rate of return on plan assets		5.00%	3.70%	3.80%
International | Pension Benefits | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 785	$ 761	$ 937

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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