Retirement-Related Benefits - Investment Strategy (Details) $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($)
United States \| Personal Pension Plan (PPP) \| Fixed-income securities
Investment Policies And Strategies
Target allocation (as a percent)	55.00%
United States \| Personal Pension Plan (PPP) \| Equity securities
Investment Policies And Strategies
Target allocation (as a percent)	15.00%
United States \| Personal Pension Plan (PPP) \| Other
Investment Policies And Strategies
Target allocation (as a percent)	30.00%
United States \| Personal Pension Plan (PPP) \| Private equities and private real estate investments
Investment Policies And Strategies
Fair Value of plan assets	$ 1,753
Commitments for future investments in private markets	$ 1,720
Non-U.S. Plans \| Maximum
Investment Policies And Strategies
Percentage of board members, elected by employees and retirees for managing investments (as a percent)	50.00%
Non-U.S. Plans \| Fixed-income securities
Investment Policies And Strategies
Target allocation (as a percent)	57.00%
Non-U.S. Plans \| Equity securities
Investment Policies And Strategies
Target allocation (as a percent)	18.00%
Non-U.S. Plans \| Other
Investment Policies And Strategies
Target allocation (as a percent)	9.00%
Non-U.S. Plans \| Insurance contracts
Investment Policies And Strategies
Target allocation (as a percent)	17.00%

Amount of commitments for future investments in private markets to be made over a number of years.

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The percentage of board members, elected by employees and retirees for managing investments.

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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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