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v3.23.1

Financial Instruments and Risk Management (Market Price Risk) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) $ / oz
Disclosure of detailed information about hedged items [line items] |  |
Unrealized gains | $ (0.3) | $ 0.4
Market risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Potential percentage change in value | 1000.00% |
Impact on other comprehensive income | $ 1.9 | 2.4
Gold Options | Market risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Potential percentage change in value | 10.00% |
Impact on pre-tax earnings | $ 81.2 | $ 81.2
Bottom of range | Gold Options | Market risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz |  | 1,629
Top of range | Gold Options | Market risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz |  | 2,039

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