Supplemental Cashflow Information (Schedule of significant non-cash financing and investing transactions) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Supplemental Cashflow Information [abstract]
Acquisition of Roxgold	$ 594,666
Mineral properties, plant and equipment changes in closure and reclamation provision	(3,729)	$ (9,339)
Stock options allocated to share capital upon exercise	136	427
Additions on right of use assets	(2,551)	(2,715)
Fair value of share units allocated to share capital upon settlement	$ 4,468	$ 3,081

Noncash financing and investing transaction related to acquisitions.

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Noncash financing and investing transaction related to fair value of stock options upon exercise.

No definition available.

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Noncash financing and investing transaction related to property, plant and equipment.

No definition available.

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Noncash financing and investing transactions related to right of use assets.

No definition available.

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Noncash financing and investing transactions related to share units allocated to reserve upon settlement.

No definition available.

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No definition available.

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