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Amount of interest expense on operating lease liability.

No definition available.

Name:	mux_OperatingLeaseInterestExpense
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Amount of amortization expense attributable to right-of-use asset from operating lease.

No definition available.

Name:	mux_OperatingLeaseRightOfUseAssetAmortization
Namespace Prefix:	mux_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Amount of amortization expense attributable to right-of-use asset from finance lease.

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- References

No definition available.

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Data Type:	xbrli:stringItemType
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Amount of operating lease expense. Excludes sublease income.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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