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v3.25.3

Retirement Benefits - Net Periodic Benefit Cost (Details) - Pension Plan [Member] - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Settlements |  |  |  | $ 82 |
United States [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Service cost | $ 10 |  | $ 11 | 30 | $ 32
Interest cost | 32 |  | 49 | 100 | 147
Expected return on plan assets | (51) |  | (76) | (157) | (227)
Settlements | 1 | $ 82 | 0 | 83 | 0
Amortization of net loss | 7 |  | 9 | 23 | 27
Amortization of prior service credit | 0 |  | 0 | 0 | 0
Net periodic benefit cost/(income) | (1) |  | (7) | 79 | (21)
United Kingdom [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Service cost | 1 |  | 1 | 4 | 4
Interest cost | 31 |  | 29 | 91 | 86
Expected return on plan assets | (44) |  | (40) | (131) | (119)
Settlements | 0 |  | 0 | 3 | 0
Amortization of net loss | 16 |  | 14 | 47 | 41
Amortization of prior service credit | (2) |  | (3) | (4) | (9)
Net periodic benefit cost/(income) | 2 |  | 1 | 10 | 3
Other Foreign Plans [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Service cost | 3 |  | 4 | 10 | 12
Interest cost | 7 |  | 7 | 20 | 20
Expected return on plan assets | (12) |  | (11) | (34) | (32)
Settlements | 0 |  | 0 | 0 | 0
Amortization of net loss | 1 |  | 0 | 1 | 1
Amortization of prior service credit | 0 |  | 1 | 0 | 1
Net periodic benefit cost/(income) | $ (1) |  | $ 1 | $ (3) | $ 2

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