INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Changes in Company's Investment in MSC (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Change in the investment in MSC
Investment in MSC, beginning of period			$ 108,326
Income tax recovery	$ 841	$ 152	3,878	$ 1,276
Dividend distribution received			(7,561)	(282)
Investment in MSC, end of period	95,688		95,688		$ 108,326
Minera Santa Cruz S.A. [Member]
Change in the investment in MSC
Investment in MSC, beginning of period			108,326	110,183	110,183
Attributable net income from MSC			93		2,745
Amortization of fair value increments			(5,571)		(5,390)
Income tax recovery			401		1,128
Dividend distribution received			(7,561)		(340)
Investment in MSC, end of period	$ 95,688		95,688		$ 108,326
Dividends received			$ 7,600	$ 300

Represents the amortization of fair value increments from the equity method investments.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of the period.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee, before amortization, to which the equity method of accounting is applied.

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No definition available.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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Dividends received on equity and other investments during the current period.

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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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