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IMPAIRMENT (Details 3) - Individual assets or cash-generating units [member] $ in Millions | Dec. 31, 2018 USD ($)
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$100 per ounce change in gold price [Member] | Rainy River Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | $ 256.6
$100 per ounce change in gold price [Member] | Blackwater Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 0.0
0.5% change in discount rate [Member] | Rainy River Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 24.7
0.5% change in discount rate [Member] | Blackwater Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 0.0
5% change in foreign exchange rate [Member] | Rainy River Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 103.4
5% change in foreign exchange rate [Member] | Blackwater Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 0.0
5% change in operating costs [Member] | Rainy River Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 106.6
5% change in operating costs [Member] | Blackwater Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 0.0
5% change in in-situ ounces [Member] | Rainy River Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | 10.9
5% change in in-situ ounces [Member] | Blackwater Mines [Member] |
Impairment [Line Items] |
Recoverable Amount | $ 16.4

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