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v3.25.3

Employee Benefit Plans (Components of Provision for Net Periodic Benefit (Credit) Cost) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Pension Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | $ 19 | $ 19 | $ 57 | $ 63
Interest cost | 108 | 107 | 325 | 324
Expected return on plan assets | (170) | (200) | (508) | (611)
Amortization of prior service cost (credit) | 1 | 1 | 1 | 1
Amortization of net actuarial (gain) loss | 0 | (23) | 0 | (171)
Curtailments | 0 | 0 | 0 | (56)
Plan amendment | 0 | 0 | 0 | 22
Net periodic benefit (credit) cost | (42) | (96) | (125) | (428)
Other Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 3 | 2 | 8 | 8
Interest cost | 13 | 15 | 42 | 43
Expected return on plan assets | (39) | (43) | (119) | (128)
Amortization of prior service cost (credit) | (6) | (9) | (19) | (27)
Amortization of net actuarial (gain) loss | 0 | 11 | 0 | (58)
Curtailments | 0 | 0 | 0 | (4)
Plan amendment | 0 | 0 | 0 | 0
Net periodic benefit (credit) cost | $ (29) | $ (24) | $ (88) | $ (166)

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