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IMPAIRMENT AND REVERSAL OF NON-CURRENT ASSETS - Narrative (Details) |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 09, 2017 USD ($) | Mar. 28, 2017 USD ($) | Jun. 30, 2018 USD ($) Rate | Dec. 31, 2017 USD ($) | Mar. 31, 2017 USD ($) | Dec. 31, 2017 | Jun. 30, 2017 | Dec. 31, 2018 USD ($) $ / pound $ / ounce Rate | Dec. 31, 2017 USD ($) | Dec. 31, 2015 USD ($)
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 900,000,000 | $ (212,000,000) |
Estimated change in WACC (as percent) |  |  |  |  |  |  |  | 1.00% |  |
Cerro Casale |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment loss (reversal of loss) |  |  |  |  | $ (1,120,000,000) |  |  |  |  |
Implied fair value from consideration received in deconsolidation |  | $ 1,200,000,000 |  |  |  |  |  |  |  |
Non-current assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 746,000,000 |  |
Goodwill |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 154,000,000 | 0 |
Bulyanhulu | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 0 | 740,000,000 |
Veladero[Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Duty on export | Rate |  |  |  |  |  |  |  | 12.00% |  |
Capped price per USD export |  |  |  |  |  |  |  | $ 4.00 |  |
Veladero[Member] | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 246,000,000 | 0 |
Gains (losses) on subsequent increase in fair value less costs to sell not in excess of recognised cumulative impairment loss or write-down to fair value less costs to sell |  |  |  |  |  |  |  | 674,000,000 |  |
Veladero[Member] | Goodwill |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 154,000,000 | 0 |
Percentage of entity's revenue | Rate |  |  |  |  |  |  |  | 1.50% |  |
Lagunas Norte | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Discount rate used in current measurement of fair value less costs of disposal | Rate |  |  |  |  |  |  |  | 3.80% |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 405,000,000 | 3,000,000 |
Gains (losses) on subsequent increase in fair value less costs to sell not in excess of recognised cumulative impairment loss or write-down to fair value less costs to sell |  |  |  |  |  |  |  | 150,000,000 |  |
Estimated gold price |  |  |  |  |  |  |  | 1,200 |  |
Lagunas Norte | Inventories [member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 166,000,000 |  |
Estimated gold price |  |  |  |  |  |  |  | 1,250 |  |
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 |  |  |  |  |  |  |  | (7,000,000) | 407,000,000 |
Pascua-Lama | Non-current assets | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  | $ (429,000,000) |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  |  | 850,000,000 |  |
Lumwana [Member] | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 0 | $ (259,000,000) |
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) | $ / pound |  |  |  |  |  |  |  | 0.25 |  |
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 |  |
Estimated change in WACC (as percent) |  |  |  |  |  |  |  | 1.00% |  |
Gold[member] | Veladero |  |  |  |  |  |  |  |  |  |
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 |  |
Lumwana [Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Change in royalty rate | Rate |  |  |  |  |  |  |  | 1.50% |  |
Duty on export | Rate |  |  |  |  |  |  |  | 5.00% |  |
Royalty tax rate | Rate |  |  |  |  |  |  |  | 10.00% |  |
Lumwana [Member] | Individual assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  | (259,000,000) |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  |  | $ 747,000,000 |  |
Acacia Mining PLC |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Discount rate used in current measurement of fair value less costs of disposal | Rate |  |  |  |  |  |  |  | 11.00% |  |
Proportion of ownership interest in subsidiary |  |  |  |  |  |  |  | 63.90% |  |
Acacia Mining PLC | Bulyanhulu | Non-current assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  | $ (740,000,000) |  |  |  | $ 0 |  |
Recoverable amount |  |  |  |  |  |  |  | $ 600,000,000 |  |
Recoverable amount of asset or cash generating unit, percent of asset basis |  |  |  |  |  |  |  | 100.00% |  |
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% |  |
Cerro Casale |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Proportion of ownership interest sold | 25.00% | 25.00% |  |  |  |  |  | 25.00% |  |
Proportion of ownership in joint operation | 50.00% |  |  |  |  |  |  | 50.00% |  |
Implied fair value from consideration received in deconsolidation | $ 1,200,000,000 |  |  |  |  |  |  |  |  |
Proportion of ownership interest in subsidiary | 50.00% |  |  |  |  |  |  |  |  |
Minimum | Gold[member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Discount rate used in current measurement of fair value less costs of disposal |  |  |  | 3.00% |  | 3.00% |  | 3.00% | 3.00% |
Maximum | Gold[member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Discount rate used in current measurement of fair value less costs of disposal |  |  |  | 6.00% |  | 6.00% |  | 11.00% | 6.00% |
$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] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ (139,000) |  |
$100 Decrease in Gold Price | Gold[member] | Veladero |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 186,000,000 |  |
$100 Decrease in Gold Price | Acacia Mining PLC |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 98 |  |
$100 Decrease in Gold Price | Pueblo Viejo | Gold[member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | (791,000) |  |
$100 Increase in Gold Price | Gold[member] | Veladero |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ (184,000,000) |  |
$100 Increase in Gold Price | Acacia Mining PLC |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Estimated change in WACC (as percent) | Rate |  |  |  |  |  |  |  | 1.00% |  |
$100 Increase in Gold Price | Pueblo Viejo | Gold[member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 607,000 |  |
$0.25 decrease in copper [Member] | Lumwana [Member] | Copper |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 426,000,000 |  |
Cash-generating units | Bulyanhulu |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Carrying Value |  |  |  |  |  |  |  | 588,000,000 |  |
Cash-generating units | Lumwana [Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Carrying Value |  |  |  |  |  |  |  | 735,000,000 |  |
Cash-generating units | Lagunas Norte |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Carrying Value |  |  |  |  |  |  |  | 0 |  |
Cash-generating units | Pueblo Viejo |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Carrying Value |  |  |  |  |  |  |  | 2,863,000,000 |  |
Tax contingent liability | Tanzanian Revenue Authority Assessment | Acacia Mining PLC |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Royalty tax rate |  |  |  |  |  | 4.00% | 6.00% |  |  |
Clearing fee on minerals exported |  |  |  |  |  | 1.00% |  |  |  |
OreCorp [Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  | $ 24 |  |  |  |  |  |  |
Recoverable amount |  |  |  |  |  |  |  | $ 10 |  |
Proportion of ownership interest sold | Rate |  |  |  |  |  |  |  | 51.00% |  |
Future consideration to be received |  |  |  |  |  |  |  | $ 7 |  |
Net smelter royalty capped |  |  |  |  |  |  |  | $ 15 |  |
Proportion of ownership in joint operation | Rate |  |  |  |  |  |  |  | 49.00% |  |
Consideration paid (received) |  |  |  |  |  |  |  | $ 3 |  |
Kabanga [Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  | $ 30,000,000 |  |  |  |  | (30,000,000) |  |
Proportion of ownership interest in associate | Rate |  |  | 50.00% |  |  |  |  |  |  |
One percent decrease in WACC [Member] | Gold[member] | Veladero | Non-current assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | 42,000,000 |  |
One percent decrease in WACC [Member] | Pueblo Viejo | Gold[member] | Non-current assets |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Impairment (reversals) charges |  |  |  |  |  |  |  | $ 540,000,000 |  | $ 0
One percent increase in WACC [Member] | Veladero[Member] |  |  |  |  |  |  |  |  |  |
Disclosure of information for impairment loss recognised or reversed for individual asset or cash-generating unit [line items] |  |  |  |  |  |  |  |  |  |
Estimated change in WACC (as percent) |  |  |  |  |  |  |  | 1.00% |  |

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