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IMPAIRMENT AND REVERSAL OF NON-CURRENT ASSETS - Narrative (Details) |  |  |  |  | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 25, 2020 | Jan. 24, 2020 USD ($) $ / ounce | Jan. 01, 2020 | Sep. 17, 2019 shares | Dec. 31, 2020 USD ($) | Sep. 30, 2020 Rate | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) Rate | Jun. 30, 2020 Rate | Jun. 30, 2019 USD ($) Rate | Sep. 30, 2020 | Sep. 30, 2019 Rate | Dec. 31, 2020 USD ($) $ / ounce Rate | Dec. 31, 2019 USD ($) $ / ounce | Jul. 19, 2019 shares | May 21, 2019 USD ($) Rate shares | Sep. 28, 2018 Rate
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  | 16.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (269,000,000) | $ (1,423,000,000) |  |  |
Non-current 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) |  |  |
Bulyanhulu [Member] | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  | $ 1,237,000,000 |  |  |  |  |  |  |  |  |  |  |
Reversal of impairment loss |  |  |  |  |  |  | 663,000,000 |  |  |  |  |  |  |  |  |  |  |
North Mara [Member] | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  | 967,000,000 |  |  |  |  |  |  |  |  |  |  |
Reversal of impairment loss |  |  |  |  |  |  | 46,000,000 |  |  |  |  |  |  |  |  |  |  |
Pascua-Lama | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  |  | $ 398,000,000 |  |  |  |  |  |  | 398,000,000 |  |  |
Lumwana | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets |  |  |  |  |  |  |  |  | 10.40% |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  | $ (947,000,000) |  |  |  |  | $ 0 | (947,000,000) |  |  |
Fair Value Less Cost of Disposal |  |  |  |  |  |  |  |  | $ 1,400,000,000 |  |  |  |  |  |  |  |  |
Nevada Gold Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary |  |  |  |  |  |  |  |  |  |  |  |  |  | 61.50% |  |  |  |
Nevada Gold Mines [Member] | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60,000,000 |  |  |
Acacia Mining PLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 787,000,000 |
Proportion of ownership interests held by non-controlling interests | Rate |  |  |  |  |  |  |  |  |  |  |  |  | 36.10% |  |  |  |  |
Estimated Mineral Price For Measurement Of Fair Value Less Costs Of Disposal |  |  |  |  |  |  |  |  |  |  | 1,250 |  |  |  |  |  |  |
Share for share exchange | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.168 | 0.153 |
Percent of ownership request for consideration | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |
Percent share in economic benefit | Rate |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |
Pueblo Viejo | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000 | (865,000,000) |  |  |
Risk Premium used for adjustment due to non-financial risk |  |  |  |  | 2.00% |  |  |  |  |  |  |  |  | 2.00% |  |  |  |
Porgera |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  | $ 297,000,000 |  |  |  |  |  |  |  |  | $ 297,000,000 |  |  |  |
Tanzanian Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  | 16.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) through changes in ownership interests in subsidiaries that do not result in loss of control, equity |  |  |  |  |  |  | 238,000,000 |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  | 304,000,000 |  |  |  |
Loss (gain) on assignment of shareholder loans |  |  |  |  |  |  | $ 167,000,000 |  |  |  |  |  |  |  |  |  |  |
Tanzanian Mines [Member] | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (304,000,000) | 0 |  |  |
Loulo Gounkoto |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary |  |  |  |  |  |  |  |  |  |  |  |  |  | 80.00% |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.00% |  |  |  |
Lumwana |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase in royalty rate | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.50%
Royalty on copper production | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.00%
Duty on export | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.00%
Lumwana | Copper |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated change in mineral price (gold, in dollars per ounce; copper, in dollars per pound) | Rate |  |  |  |  |  | 3.00 |  |  | 3.00 | 2.85 |  |  |  |  |  |  |  |
Pascua-Lama | Individual assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 296,000,000 |  |  |
Acacia Mining PLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary |  |  |  |  | 100.00% |  |  | 100.00% |  |  |  | 63.90% |  | 84.00% |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  |  | 36.10% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share for share exchange | shares |  |  |  | 0.168 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pueblo Viejo |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary |  |  |  |  |  |  |  |  |  |  |  |  |  | 60.00% |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |
Porgera |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary | 47.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum | Tanzanian Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
NAV multiple |  | $ 1.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets |  | 5.40% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum | Tanzanian Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
NAV multiple |  | $ 1.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets |  | 6.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term [Member] | Tanzanian Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Mineral Price For Measurement Of Fair Value Less Costs Of Disposal | $ / ounce |  | 1,300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term [Member] | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Mineral Price For Measurement Of Fair Value Less Costs Of Disposal | $ / ounce |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400 | 1,300 |  |  |
Short-term [Member] | Tanzanian Mines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Mineral Price For Measurement Of Fair Value Less Costs Of Disposal | $ / ounce |  | 1,350 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term [Member] | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Mineral Price For Measurement Of Fair Value Less Costs Of Disposal | $ / ounce |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,700 | 1,350 |  |  |
$100 Decrease in Gold Price | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated change in mineral price (gold, in dollars per ounce; copper, in dollars per pound) | $ / ounce |  |  |  |  |  |  |  |  |  |  |  |  |  | 100 |  |  |  |
$100 Decrease in Gold Price | Loulo Gounkoto | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Fair Value of Asset Impairment |  |  |  |  | $ 493,000,000 |  |  |  |  |  |  |  |  | $ 493,000,000 |  |  |  |
$100 Decrease in Gold Price | Veladero [Member] | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Fair Value of Asset Impairment |  |  |  |  | 207,000,000 |  |  |  |  |  |  |  |  | $ 207,000,000 |  |  |  |
Increase/decrease in gold/copper price [Member] | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated change in mineral price (gold, in dollars per ounce; copper, in dollars per pound) | $ / ounce |  |  |  |  |  |  |  |  |  |  |  |  |  | 100 |  |  |  |
Cash-generating units | Veladero [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  | 779,000,000 |  |  |  |  |  |  |  |  | $ 779,000,000 |  |  |  |
Cash-generating units | Loulo Gounkoto |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recoverable amount |  |  |  |  | 4,187,000,000 |  |  |  |  |  |  |  |  | 4,187,000,000 |  |  |  |
One percent increase in WACC [Member] | Veladero [Member] | Gold[member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Fair Value of Asset Impairment |  |  |  |  | $ 134,000,000 |  |  |  |  |  |  |  |  | $ 134,000,000 |  |  |  |
One percent increase/decrease in WACC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |
One percent decrease in WACC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets | Rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |
Minimum | Acacia Mining PLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
NAV multiple |  |  |  |  |  |  |  |  |  |  | $ 1.0 |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets | Rate |  |  |  |  |  |  |  |  |  |  | 6.50% |  |  |  |  |  |  |
Maximum | Acacia Mining PLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
NAV multiple |  |  |  |  |  |  |  |  |  |  | $ 1.1 |  |  |  |  |  |  |
Weighted average cost of capital, significant unobservable inputs, assets | Rate |  |  |  |  |  |  |  |  |  |  | 6.90% |  |  |  |  |  |  |

X
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- Definition Estimated change in mineral price used In current measurement of fair value less costs of disposal + References No definition available. + Details
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- Definition Estimated mineral price for measurement of fair value less costs Of disposal + References No definition available. + Details
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- Definition Loss (gain) on assignment of shareholder loans + References No definition available. + Details
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- Definition Net asset value multiple used in current measurement of fair value less costs of disposal + References No definition available. + Details
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- Definition Percent of ownership request for consideration + References No definition available. + Details
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