Pensions and other benefit plans - Projected Future Minimum Contributions to the Company's U.S. and International Unfunded Retirement Plans (Details) $ in Millions	Dec. 31, 2023 USD ($)
Retirement Benefits [Abstract]
2024	$ 122
2025	126
2026	133
2027	139
2028	145
2029-2033	$ 787

Defined benefit plan expected future benefit contribution in five fiscal years thereafter.

No definition available.

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Defined benefit plan expected future benefit contribution in year five.

No definition available.

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Defined benefit plan expected future benefit contribution in year four.

No definition available.

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Defined benefit plan expected future benefit contribution in year one.

No definition available.

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Defined benefit plan expected future benefit contribution in year three.

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Defined benefit plan expected future benefit contribution in year two.

No definition available.

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No definition available.

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