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Employee Benefits - Amounts Recognized in the Consolidated Statements of Financial Position (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Prepaid benefit cost | $ 556 | $ 618
Pension Plan | U.K. |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Prepaid benefit cost | 505 | 570
Accrued benefit liability - current | (1) | (1)
Accrued benefit liability - non-current | (26) | (27)
Accumulated other comprehensive loss | 1,897 | 1,909
Net amount recognized | 2,375 | 2,451
Pension Plan | Other |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Prepaid benefit cost | 0 | 1
Accrued benefit liability - current | (4) | (4)
Accrued benefit liability - non-current | (51) | (57)
Accumulated other comprehensive loss | 414 | 431
Net amount recognized | 359 | 371
Pension Plan | U.S. |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Prepaid benefit cost | 0 | 0
Accrued benefit liability - current | (42) | (42)
Accrued benefit liability - non-current | (573) | (658)
Accumulated other comprehensive loss | 1,276 | 1,319
Net amount recognized | $ 661 | $ 619

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