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IMPAIRMENT AND REVERSAL OF NON-CURRENT ASSETS - Assumptions (Details)
 12 Months Ended
Dec. 31, 2020
USD ($)
$ / pound
Dec. 31, 2019
USD ($)
$ / pound
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
Impairment (reversals) charges $ (269,000,000) $ (1,423,000,000)
Gold[member]    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
LOM year 20 years 19 years
Gold[member] | Average    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
NAV multiple $ 1.3 $ 1.2
WACC 5.00% 4.00%
Gold[member] | Minimum    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
WACC 3.00% 3.00%
Gold[member] | Maximum    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
WACC 12.00% 7.00%
Long-term | Copper    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
Mineral price (gold, in dollars per ounce; copper, in dollars per pound) | $ / pound 3.00 3.00
Impairment (reversals) of long lived assets    
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items]    
Impairment (reversals) charges $ (269,000,000) $ (1,423,000,000)