Financing arrangements - Debt Extinguishment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Repayments of debt	$ 5,000	$ 3,600	$ 1,454
Extinguishment of debt	683	659	647
Gain (loss) on extinguishment of debt	264	215	225
Notes
Debt Instrument [Line Items]
Repayments of debt	500	3,600
Various Long-Term Notes \| Notes
Debt Instrument [Line Items]
Repayments of debt	$ 1,000	$ 875	$ 881
2.00% notes due 2032 (2.00% 2032 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	2.00%		2.00%
3.15% notes due 2040 (3.15% 2040 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	3.15%	3.15%	3.15%
2.80% notes due 2041 (2.80% 2041 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	2.80%	2.80%	2.80%
3.375% notes due 2050 (3.375% 2050 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	3.375%	3.375%	3.375%
3.00% notes due 2052 (3.00% 2052 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	3.00%	3.00%	3.00%
4.20% notes due 2052 (4.20% 2052 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	4.20%	4.20%	4.20%
4.40% notes due 2062 (4.40% 2062 Notes) \| Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	4.40%	4.40%	4.40%
Term loan due October 2026 \| Notes
Debt Instrument [Line Items]
Repayments of debt		$ 200

Contractual interest rate for funds borrowed, under the debt agreement.

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