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Financial Instruments and Risk Management (Gold Option Contracts) (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) $ / oz oz | Dec. 31, 2021 USD ($)
Disclosure of detailed information about hedged items [line items] |  |
Unrealized gains | $ (0.3) | $ 0.4
Gold Options | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Financial assets, at fair value |  | 0.5
Gains (losses) on change in fair value of derivatives | (3.5) | (0.5)
Unrealized gains | $ 0.3 | $ 0.9
Gold Options | 2018 | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Ounces subject to contract | oz | 44,100 |
Purchase Put Options | Gold Options | 2018 | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz | 1,755 |
Sold Call Option | Gold Options | 2018 | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz | 2,144 |

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