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Inventory (Tables) | 12 Months Ended
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Dec. 31, 2018
Disclosure of inventories [Abstract] |
Schedule of Inventory |
| December 31, 2018 | December 31, 2017
In-process precious metals | $53.6 |  | $131.6 |
Ore in stockpiles | 35.4 |  | 44.1 |
Parts and supplies | 45.7 |  | 41.5 |
Dore, refined precious metals and gold in concentrate | 5.5 |  | 12.7 |
| 140.2 |  | 229.9 |
Less: Long-term inventory | (30.0 | ) | (68.7 | )
| $110.2 |  | $161.2 |

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