Financial risk management - D.2.1. Debt denominated in US Dollars and other currencies (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	$ 6,886	$ 5,815
Reasonably possible change in risk variable, percent	1.00%
Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	$ 6,886	5,815
Reasonably possible change in risk variable, percent	10.00%
Reasonably possible increase (decrease) in risk variable, impact on profit before tax	$ (81)	(8)
Debt denominated in US dollars \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	3,293	3,429
Total debt denominated in other currencies \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	3,592	2,386
Guatemala \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	865	496
Colombia \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	620	554
Bolivia \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	128	153
Paraguay \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	565	233
El Salvador \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	248	71
Panama \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	734	734
Luxembourg (COP denominated) \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	0	33
Ecuador \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	83
Uruguay \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	201
Costa Rica \| Foreign currency risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Debt	$ 148	$ 113

The amount of outstanding funds that the entity is obligated to repay.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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