v3.25.4

Retirement Benefits (Narrative) (Details) shares in Millions, $ in Millions, £ in Billions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 01, 2017 | Sep. 30, 2025 USD ($) | Sep. 30, 2025 GBP (£) | Dec. 31, 2025 USD ($) shares | Dec. 31, 2024 USD ($) definedBenefitSection | Dec. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Assumed health care cost trend rate for medicare eligibles and non-medicare eligibles |  |  |  | 5.43% |  |
Future assumed health care cost trend rate |  |  |  | 5.11% |  |
Automatic company contribution (as a percent) | 4.00% |  |  |  |  |
401(k) Plan's assets invested in common stock |  |  |  | $ 580 | $ 737 |
Pension Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Invested in insurance policy will reimburse fund for all future benefit payments |  | $ 2,500 | £ 1.9 |  |  |
United States |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Assumed health care cost trend rate for medicare eligibles and non-medicare eligibles |  |  |  | 8.60% |  |
Future assumed health care cost trend rate |  |  |  | 4.00% |  |
Cap on employer share of health care trend (as a percent) |  |  |  | 5.00% |  |
Cost of defined contribution plans |  |  |  | $ 208 | 188 | $ 173
United States | Nonqualified Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Expected employer contributions, next fiscal year |  |  |  | 34 |  |
United States | Qualified Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Expected employer contributions, next fiscal year |  |  |  | 33 |  |
Employer contributions |  |  |  | 2 |  |
United States | Pension Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Accumulated benefit obligation for plans with accumulated benefit obligations in excess of plan assets |  |  |  | 4,600 | 4,600 |
Aggregate fair value of plan assets for plans with accumulated benefit obligations in excess of plan assets |  |  |  | 4,100 | 4,100 |
Projected benefit obligation for plans with projected benefit obligations in excess of plan assets |  |  |  | 4,600 | 4,600 |
Fair value of plan assets for plans with projected benefit obligations in excess of plan assets |  |  |  | 4,100 | 4,100 |
Employer contributions |  |  |  | $ 38 | 34 |
United States | Post-retirement Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Number of shares held in defined benefit plan (in shares) | shares |  |  |  | 1 |  |
Change in plan assets (as a percent) |  |  |  | 4.50% |  |
Employer contributions |  |  |  | $ 5 | 5 |
Non-U.S. |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Accumulated benefit obligation for plans with accumulated benefit obligations in excess of plan assets |  |  |  | 436 | 462 |
Aggregate fair value of plan assets for plans with accumulated benefit obligations in excess of plan assets |  |  |  | 222 | 248 |
Projected benefit obligation for plans with projected benefit obligations in excess of plan assets |  |  |  | 532 | 564 |
Fair value of plan assets for plans with projected benefit obligations in excess of plan assets |  |  |  | 275 | 312 |
Expected employer contributions, next fiscal year |  |  |  | 39 |  |
Non-U.S. | Pension Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Employer contributions |  |  |  | 44 | 59 |
Non-U.S. | Post-retirement Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Employer contributions |  |  |  | $ 3 | $ 3 |
United Kingdom |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Period between legally-prescribed negotiations between the company and the plans' trustee |  |  |  | 3 years |  |
Number of segregated benefit pension fund | definedBenefitSection |  |  |  |  | 4 |
Cost of defined contribution plans |  |  |  | $ 183 | $ 170 | $ 158
United Kingdom | United Kingdom Pension and Postretirement Benefit Plan, Defined Benefit | Geographic Concentration Risk |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Concentration risk (as a percent) |  |  |  | 78.00% |  |
Equities and Equity Alternatives | United States |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 50.00% |  |
Actual asset allocation percentage |  |  |  | 50.00% |  |
Equities and Equity Alternatives | United States | Minimum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 46.00% |  |
Equities and Equity Alternatives | United States | Maximum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 54.00% |  |
Equities and Equity Alternatives | United Kingdom |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 7.00% |  |
Actual asset allocation percentage |  |  |  | 8.00% |  |
Fixed Income | United States |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 50.00% |  |
Actual asset allocation percentage |  |  |  | 50.00% |  |
Fixed Income | United States | Minimum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 46.00% |  |
Fixed Income | United States | Maximum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 54.00% |  |
Fixed Income | United Kingdom |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Target asset allocation percentage |  |  |  | 93.00% |  |
Actual asset allocation percentage |  |  |  | 92.00% |  |

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