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IMPAIRMENT (Details 2) - Individual assets or cash-generating units [member] $ in Millions | Dec. 31, 2017 USD ($)
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$100 per ounce change in gold price [Member] |
Impairment [Line Items] |
Recoverable Amount | $ 235.1
0.5% change in discount rate [Member] |
Impairment [Line Items] |
Recoverable Amount | 25.9
5% change in exchange rate [Member] |
Impairment [Line Items] |
Recoverable Amount | 106.5
5% change in operating costs [Member] |
Impairment [Line Items] |
Recoverable Amount | 90.3
5% change in in-situ ounces [Member] |
Impairment [Line Items] |
Recoverable Amount | $ 20.2

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