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

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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Namespace Prefix:	mux_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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-Publisher FASB
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-Paragraph 1
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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

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Balance Type:	debit
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- Details

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Period Type:

- Details

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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, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Change in the investment in MSC
Investment in MSC, beginning of period			$ 90,961
Income tax recovery	$ 524	$ 841	1,339	$ 3,878
Investment in MSC, end of period	92,824		92,824		$ 90,961
Minera Santa Cruz S.A. [Member]
Change in the investment in MSC
Dividend distribution received			(286)	(7,561)	(9,832)
Minera Santa Cruz S.A. [Member]
Change in the investment in MSC
Investment in MSC, beginning of period			90,961	108,326	108,326
Attributable net income from MSC			4,610		132
Amortization of fair value increments			(2,929)		(8,331)
Income tax recovery			468		666
Investment in MSC, end of period	$ 92,824		92,824		$ 90,961
Dividends received			$ 300	$ 7,600