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DERIVATIVE INSTRUMENTS (Details 3) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
(LOSS) Gain on swap contracts |  |
Realized | $ 12.6 | $ (18.8)
Unrealized | 0.9 | (6.1)
Total gain (loss) | 13.5 | (24.9)
Gold [Member] |  |
(LOSS) Gain on swap contracts |  |
Realized | 1.3 | (2.0)
Unrealized | (0.8) | (0.3)
Total gain (loss) | 0.5 | (2.3)
Copper [Member] |  |
(LOSS) Gain on swap contracts |  |
Realized | 11.3 | (16.8)
Unrealized | 1.7 | (5.8)
Total gain (loss) | $ 13.0 | $ (22.6)

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- Definition The gains (losses) on swap contracts which realised duirng the reporting period. + References No definition available. + Details
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- Definition The gains (losses) on swap contracts which recognised as unrealised duirng the reporting period. + References No definition available. + Details
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- Details
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