EARNINGS PER ORDINARY SHARE - Earnings per ordinary share (Details) - $ / shares shares in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings per share [abstract]
Basic weighted number of shares	874	890	894
Dilutive impact of share options outstanding	1	3	5
Diluted weighted average number of shares	875	893	899
Basic	$ 0.878	$ 0.881	$ 0.459
Diluted	0.877	0.878	0.456
Adjusted	$ 0.945	$ 0.826	$ 0.851

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]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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 number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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The earnings per share calculated using the basic weighted number of shares.

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