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Supplemental Cash Flow Information (Other Non-cash Items) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure of Cash Flow Statement [Abstract] |  |
Unrealized loss on non-hedging derivatives | $ 0.4 | $ 0.3
Payment for reclamation activities | (0.9) | 0.0
Reduction of obligation to renounce flow-through exploration expenditures | (0.6) | (2.3)
Loss on disposal of assets | 6.1 | 1.9
Payment of transaction costs incurred by Richmont Mines (note 5) | 0.0 | (5.9)
Share-based payments related to Richmont Mines transaction (note 5) | 0.0 | 1.3
Other non-cash items | 0.5 | 3.3
Other adjustments for non-cash items | $ 5.5 | $ (1.4)

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- Definition Noncash Gain on Termination of Retained Interest Royalty + References No definition available. + Details
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