The amounts payable resulting from related party transactions. [Refer: Related parties [member]]

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The proportion of ownership interest in a joint venture attributable to the entity. [Refer: Joint ventures [member]]

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The percentage of Fresnillo investment in MAG Silver Corp. common shares.

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The net smelter returns royalty percentage applicable for a mining location.

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The percent interest in acquisition of mineral property.

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Note 13 - Related Party Transactions (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Feb. 26, 2004	Dec. 31, 2018	Dec. 31, 2017
Minera Juanicipio, S.A. de C.V. [member]
Statement Line Items [Line Items]
Proportion of ownership interest in joint venture		44.00%
Fresnillo PLC [member] \| Minera Juanicipio, S.A. de C.V. [member]
Statement Line Items [Line Items]
Proportion of ownership interest in joint venture		56.00%
Fresnillo PLC [member] \| MAG Silver Corporation [member]
Statement Line Items [Line Items]
Fresnillo investment in MAG Silver Corp. common shares		11.40%
Cascabel and IMDEX [member]
Statement Line Items [Line Items]
Amounts payable, related party transactions		$ 107	$ 286
Cascabel [member] \| Cinco de Mayo property [member]
Statement Line Items [Line Items]
Net Smelter Returns Royalty Percentage	2.50%
Percentage interest in acquisition of mineral property	100.00%