Earnings (Loss) per Ordinary Share - Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic earnings (loss) per ordinary share
Basic earnings (loss) per ordinary share (dollars per share)	$ (0.03)	$ 0.32	$ (0.46)
Basic earnings (loss) per ordinary share - Continuing operations (dollars per share)	0.87	0.52	0.35
Basic earnings (loss) per ordinary share - Discontinued operations (dollars per share)	$ (0.90)	$ (0.20)	$ (0.81)
Profits (losses) attributable to equity shareholders - continuing operations	$ 364	$ 216	$ 145
Profits (losses) attributable to equity shareholders - discontinued operations	$ (376)	$ (83)	$ (336)
Weighted average number of shares (in shares)	418,349,777	417,122,155	415,440,077
Diluted earnings (loss) per ordinary share
Diluted earnings (loss) per ordinary share (dollars per share)	$ (0.03)	$ 0.32	$ (0.46)
Diluted earnings (loss) per ordinary share - Continuing operations (dollars per share)	0.87	0.52	0.35
Diluted earnings (loss) per ordinary share - Discontinued operations (dollars per share)	$ (0.90)	$ (0.20)	$ (0.81)
Diluted profits (losses) attributable to equity shareholders - continuing operations	$ 364	$ 216	$ 145
Diluted profits (losses) attributable to equity shareholders - discontinued operations	$ (376)	$ (83)	$ (336)
Diluted weighted average number of shares (in shares)	418,349,777	417,379,405	415,440,077

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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Basic earnings (loss) per share from continuing operations. [Refer: Basic earnings (loss) per share; Continuing operations [member]]

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Basic earnings (loss) per share from discontinued operations. [Refer: Basic earnings (loss) per share; Discontinued operations [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), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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Diluted earnings (loss) per share from continuing operations. [Refer: Continuing operations [member]; Diluted earnings (loss) per share]

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Diluted earnings (loss) per share from discontinued operations. [Refer: Diluted earnings (loss) per share; Discontinued operations [member]]

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The profit (loss) from continuing operations attributable to ordinary equity holders of the parent equity. [Refer: Continuing operations [member]; Profit (loss) from continuing operations]

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

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

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

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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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