Basis of preparation and significant accounting policies (Details) - Minera San Xavier S.A. de C.V.	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Disclosure of subsidiaries [line items]
Principal activity of subsidiary	Reclamation
Method used to account for subsidiary	Consolidated
Country of incorporation of subsidiary	Mexico
Proportion of ownership interest in subsidiary	100.00%	100.00%

The country in which a subsidiary of the entity is incorporated. [Refer: Subsidiaries [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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