Earnings per share - EPS Data (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Earnings per share
(Loss)/profit attributable to equity holders as presented in the income statement	$ 5	$ 2		$ (10)
Less: Dividends on preferred shares (see note 26)	(6)	(6)	$ (12)	(12)
(Loss)/profit attributable to equity holders used in calculating earnings per share	$ (1)	$ (4)	$ (12)	$ (22)
Weighted average number of ordinary shares for EPS (millions)	597.7	597.7	597.7	597.6
(Loss)/earnings per share - Basic		$ (0.01)	$ (0.02)	$ (0.04)
(Loss)/profit attributable to equity holders used in calculating earnings per share - Diluted	$ (1)	$ (4)	$ (12)	$ (22)
Weighted average number of ordinary shares for EPS (millions) - Diluted	597.7	597.7	597.7	597.6
(Loss)/earnings per share - Diluted		$ (0.01)	$ (0.02)	$ (0.04)

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator).

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The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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The amount of dividends paid by the entity on shares other than ordinary shares. [Refer: Ordinary shares [member]]

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The profit (loss) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

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The profit (loss) attributable to ordinary equity holders of the parent entity, adjusted for the effects of all dilutive potential ordinary shares. [Refer: Profit (loss)]

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The profit (loss) from continuing and discontinued operations attributable to owners of the parent. [Refer: Profit (loss)]

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The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

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