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DERIVATIVE INSTRUMENTS (Details 3) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
(LOSS) Gain on swap contracts |  |
Realized | $ (18.8) | $ (6.7)
Unrealized | (6.1) | (8.9)
Total loss | (24.9) | (15.6)
Gold [Member] |  |
(LOSS) Gain on swap contracts |  |
Realized | (2.0) | (2.6)
Unrealized | (0.3) | 1.4
Total loss | (2.3) | (1.2)
Copper [Member] |  |
(LOSS) Gain on swap contracts |  |
Realized | (16.8) | (4.1)
Unrealized | (5.8) | (10.3)
Total loss | $ (22.6) | $ (14.4)

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- References No definition available. + Details
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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 during 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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