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INCOME AND MINING TAXES (Details 2) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | --- | ---
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | $ 171.6 |  | $ 224.9 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 250.3 |  | 455.2 |  |
Deferred tax liability (asset) |  | (78.7) |  | (230.3) |  | $ (275.5)
Canada [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 141.2 |  | 173.3 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (187.5) |  | (315.8) |  |
Deferred tax liability (asset) |  | (46.3) |  | (142.5) | [1] |
Canada [Member] | Property, plant and equipment,deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 60.6 |  | 92.4 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Canada [Member] | Investment tax credits government assistance [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 18.2 |  | 48.1 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Canada [Member] | Alternative minimum tax credits [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Canada [Member] | Decommissioning obligations [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 22.2 |  | 9.4 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Canada [Member] | Derivative InstrumentsHedging [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 2.9 |  | 19.8 |  |
Canada [Member] | Accrued liabilities and provisions [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 1.3 |  | 2.3 |  |
Canada [Member] | Other deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 5.6 |  | 1.3 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (6.4) |  | 0.0 |  |
Canada [Member] | Mining interests [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (144.5) |  | (276.5) |  |
Canada [Member] | British Columbia Mining Tax [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (36.6) |  | 0.0 |  |
Canada [Member] | Ontario Mining Tax [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 6.1 |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  | (35.1) |  |
Canada [Member] | Mexican Mining Royalty [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Canada [Member] | Derivative instruments,deferred liabilities [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  | (4.2) |  |
Canada [Member] | Unused tax losses [member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  | 0.0 |  |
Canada [Member] | Gold stream obligation [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 24.3 |  |  |  |
USA [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 30.4 |  | 36.7 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (62.7) |  | (112.8) |  |
Deferred tax liability (asset) |  | (32.3) |  | (76.1) | [1] |
USA [Member] | Property, plant and equipment,deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  | 0.0 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (24.0) |  |  |  |
USA [Member] | Investment tax credits government assistance [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
USA [Member] | Alternative minimum tax credits [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 27.0 |  | 15.8 |  |
USA [Member] | Decommissioning obligations [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | 5.5 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (5.7) |  |  |  |
USA [Member] | Derivative InstrumentsHedging [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | (0.1) |  |
USA [Member] | Accrued liabilities and provisions [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | (0.1) |  | 0.5 |  |
USA [Member] | Other deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | 0.1 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (3.7) |  | (16.5) |  |
USA [Member] | Mining interests [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (29.3) |  | (51.1) |  |
USA [Member] | British Columbia Mining Tax [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
USA [Member] | Ontario Mining Tax [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
USA [Member] | Mexican Mining Royalty [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
USA [Member] | Derivative instruments,deferred liabilities [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  | 0.0 |  |
USA [Member] | Unused tax losses [member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 3.5 |  | 14.9 |  |
USA [Member] | Gold stream obligation [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  |  |  |
Australia [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 | [2] | 14.0 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 | [2] | (26.1) |  |
Deferred tax liability (asset) |  | 0.0 | [2] | (12.1) | [1] |
Australia [Member] | Property, plant and equipment,deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 | [2] | 6.6 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities | [2] |  |  |  |  |
Australia [Member] | Investment tax credits government assistance [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  | [2] |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities | [2] | 0.0 |  |  |  |
Australia [Member] | Alternative minimum tax credits [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  | [2] |  |  |
Australia [Member] | Decommissioning obligations [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 | [2] | 4.1 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities | [2] | 0.0 |  |  |  |
Australia [Member] | Derivative InstrumentsHedging [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  | [2] | 0.0 |  |
Australia [Member] | Accrued liabilities and provisions [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 | [2] | 3.3 |  |
Australia [Member] | Other deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  | [2] |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 | [2] | (1.3) |  |
Australia [Member] | Mining interests [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 | [2] | (24.8) |  |
Australia [Member] | British Columbia Mining Tax [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  | [2] |  |  |
Australia [Member] | Ontario Mining Tax [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets | [2] |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Australia [Member] | Mexican Mining Royalty [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  | [2] |  |  |
Australia [Member] | Derivative instruments,deferred liabilities [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Australia [Member] | Unused tax losses [member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  | [2] | 0.0 |  |
Australia [Member] | Gold stream obligation [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets | [2] | 0.0 |  |  |  |
Mexico [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | 0.9 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (0.1) |  | (0.5) |  |
Deferred tax liability (asset) |  | (0.1) |  | 0.4 | [1] |
Mexico [Member] | Property, plant and equipment,deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  | 0.0 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Mexico [Member] | Investment tax credits government assistance [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Mexico [Member] | Alternative minimum tax credits [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Mexico [Member] | Decommissioning obligations [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Mexico [Member] | Derivative InstrumentsHedging [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  | 0.0 |  |
Mexico [Member] | Accrued liabilities and provisions [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | 0.4 |  |
Mexico [Member] | Other deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  | 0.5 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  | 5.3 |  |
Mexico [Member] | Mining interests [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Mexico [Member] | British Columbia Mining Tax [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Mexico [Member] | Ontario Mining Tax [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Mexico [Member] | Mexican Mining Royalty [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (0.1) |  | (0.4) |  |
Mexico [Member] | Derivative instruments,deferred liabilities [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Mexico [Member] | Unused tax losses [member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Mexico [Member] | Gold stream obligation [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 0.0 |  |  |  |
Total geographical area [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 171.6 |  | 224.9 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (250.3) |  | (455.2) |  |
Deferred tax liability (asset) |  | (78.7) |  | (230.3) | [1] |
Total geographical area [Member] | Property, plant and equipment,deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 60.6 |  | 99.0 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (24.0) |  |  |  |
Total geographical area [Member] | Investment tax credits government assistance [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 18.2 |  | 48.1 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | 0.0 |  |  |  |
Total geographical area [Member] | Alternative minimum tax credits [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 27.0 |  | 15.8 |  |
Total geographical area [Member] | Decommissioning obligations [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 22.2 |  | 19.0 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (5.7) |  |  |  |
Total geographical area [Member] | Derivative InstrumentsHedging [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 2.9 |  | 19.7 |  |
Total geographical area [Member] | Accrued liabilities and provisions [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 1.2 |  | 6.5 |  |
Total geographical area [Member] | Other deferred tax assets [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 5.6 |  | 1.9 |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (10.1) |  | (12.5) |  |
Total geographical area [Member] | Mining interests [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (173.8) |  | (352.4) |  |
Total geographical area [Member] | British Columbia Mining Tax [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (36.6) |  | (50.6) |  |
Total geographical area [Member] | Ontario Mining Tax [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 6.1 |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  | (35.1) |  |
Total geographical area [Member] | Mexican Mining Royalty [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  | (0.1) |  | (0.4) |  |
Total geographical area [Member] | Derivative instruments,deferred liabilities [Member] |  |  |  |  |  |
Deferred tax liabilities |  |  |  |  |  |
Deferred tax liabilities |  |  |  | (4.2) |  |
Total geographical area [Member] | Unused tax losses [member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | 3.5 |  | $ 14.9 |  |
Total geographical area [Member] | Gold stream obligation [Member] |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |
Deferred tax assets |  | $ 24.3 |  |  |  |
[1] | Prior period comparatives have been revised as per note 5.
[2] | As at December 31, 2017, the deferred tax asset and deferred tax liability at Peak Mines are included in assets held-for-sale and liabilities held-for-sale, respectively.

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