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REVENUE - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) $ / pound	Dec. 31, 2016 USD ($) $ / pound $ / ounce
Gold
Disclosure of Disaggregation of Revenue [Line Items]
Percentage of composition of principal product (as percent)	90.00%
Provisional pricing gain (loss)	$ 1	$ 0
Average price of sales subject to final settlement (copper in dollars per pound; gold in dollars per oz) | $ / ounce		1,152
Copper
Disclosure of Disaggregation of Revenue [Line Items]
Provisional pricing gain (loss)	$ 46	$ (22)
Average price of sales subject to final settlement (copper in dollars per pound; gold in dollars per oz) | $ / pound	3.29	2.51

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- Definition

Adjustments for gains (losses) on changes in the fair value of derivatives to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: At fair value [member]; Derivatives [member]; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2017-01-01
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-Note Effective 2018-01-01
-Name IFRS
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-IssueDate 2017-01-01
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