The value of the outstanding surety bonds.

No definition available.

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- Definition

Represents the percentage of annual fees on the value of the surety bonds.

+ References

No definition available.

+ Details

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- Definition

Represents a surety bond obligation. It is a promise by a surety or guarantor to pay one party (the obligee) a certain amount if a second party (the principal) fails to meet some obligation, such as fulfilling the terms of a contract.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of drew down of surety bonds.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of upfront deposit on the value of surety bonds.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Amount of noncurrent assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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COMMITMENTS AND CONTINGENCIES - Reclamation Bonds (Details) $ in Thousands, CAD in Millions						9 Months Ended
	Sep. 30, 2017 CAD	Sep. 30, 2017 USD ($)	Aug. 25, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 23, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Reclamation Bonds
Other assets		$ 11,227				$ 11,227	$ 532
Percentage of annual fees on surety bonds	2.00%	2.00%
Surety bonds upfront deposit amount		$ 0				500
Surety bonding obligation	CAD 20.6	16,500
Outstanding surety bonds		20,000				20,000
Reclamation Bonds
Reclamation Bonds
Face amount					$ 20,000
Percentage of annual fees on surety bonds					2.00%
Surety bonds upfront deposit amount			$ 15,000		$ 0
Outstanding surety bonds		19,900				19,900
Drew down			$ 15,000
Timmins
Reclamation Bonds
Surety bonds upfront deposit amount				$ 100
Other assets \| Timmins
Reclamation Bonds
Other assets		$ 100				$ 100