CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
CONSOLIDATED STATEMENTS OF CASH FLOWS
Collection of VAT taxes receivable	$ 5,864	$ 9,523

Represents information pertaining to collection of value added taxes receivable.

No definition available.

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