Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Pension plans - Defined benefit pension plans - Narrative (Detail) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 11,720	$ 12,767	$ 12,738
Amounts recognized in the Consolidated Balance Sheets:
ABO	11,200	12,300
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2025	893
2026	873
2027	875
2028	884
2029	883
2030 - 2034	4,379
Expected contribution to pension plans during the next year	114
Unfunded Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 1,000	$ 1,000