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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.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount of cost for defined contribution plan.

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Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to defined contribution savings plans		$ 223	$ 215	$ 199
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 18,700	$ 18,100
Percentage of Company's pension investments categorized as level 3 assets		3.00%	4.00%
Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 737	$ 700
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,107	1,040	$ 1,045
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		70
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		7.70%	7.75%	7.00%
United States \| Forecast \| Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	7.70%
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		15.00%
United States \| International equities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		30.00%
United States \| Fixed Income Investments \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		40.00%
United States \| Fixed Income Investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation		50.00%
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		$ 10,400	$ 10,000
Fair value of plan assets		10,730	9,717	$ 9,804
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		270
United States \| Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2	2	3
International \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		10,906	$ 9,647	$ 9,562
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		$ 190
Expected rate of return on plan assets		5.40%	5.20%	5.00%
International \| Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 735	$ 698	$ 785