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Other (Loss) Gain (Tables) | 12 Months Ended
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Dec. 31, 2020
Other Gain (Loss) [Abstract] |
Schedule of Other Nonoperating Income (Expense) | Other (loss) gain recorded in net earnings for the years ended:
|  |  | December 31, | December 31,
|  |  | 2020 | 2019
Reduction of obligation to renounce flow-through exploration expenditures |  |  | $1.0 |  | $0.6 |
Unrealized gain (loss) on non-hedging derivatives |  |  | 0.7 |  | (0.6) |
Loss on disposal of assets |  |  | (1.0) |  | (0.7) |
Gain on sale of non-core royalties |  |  | 0.6 |  | 8.0 |
Other |  |  | (5.0) |  | (2.2) |
|  |  | ($3.7) |  | $5.1 |

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- Definition Schedule of Other Nonoperating Income (Expense)1 [Table Text Block] + References No definition available. + Details
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