CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents (Note 4)	$ 78,883	$ 51,015
Marketable securities (Note 5)	12,825	21,114
Receivables, prepaids and other current assets (Note 6)	7,848	5,752
Inventories (Note 7)	27,176	26,836
Due from McEwen Copper Inc. (Note 14)	$ 3,003	$ 3,169
Other Receivable, after Allowance for Credit Loss, Current, Related Party [Extensible Enumeration]	Mcewen Copper Inc [Member]	Mcewen Copper Inc [Member]
Total current assets	$ 129,735	$ 107,886
Mineral property interests and plant and equipment, net (Note 8)	376,887	227,208
Equity method investments (Note 9)	411,759	428,641
Loan receivable from McEwen Copper Inc. (Note 14)	$ 12,440	$ 6,052
Other Receivable, after Allowance for Credit Loss, Noncurrent, Related Party [Extensible Enumeration]	Mcewen Copper Inc [Member]	Mcewen Copper Inc [Member]
Deferred tax assets	$ 22,612	$ 25,591
Inventories (Note 7)	34,036	20,560
Restricted cash (Note 4)	4,637	4,246
Other assets		34
TOTAL ASSETS	992,106	820,218
Current liabilities:
Accounts payable and accrued liabilities	41,324	44,911
Long-term debt, current portion (Note 10)	6,000
Reclamation and remediation liabilities (Note 11)	6,808	6,473
Contract liability (Note 16)	8,050	7,549
Flow-through share premium (Note 12)	231	974
Tax liabilities	448	2,976
Lease liabilities	831	926
Total current liabilities	63,692	63,809
Long-term debt, net of issuance costs (Note 10)	120,572	126,168
Reclamation and remediation liabilities (Note 11)	39,379	39,384
Deferred tax liabilities	58,738	40,328
Lease liabilities	995	1,088
Other liabilities	2,094	3,204
Total liabilities	285,470	273,981
Shareholders' equity:
Common shares: 59,744 as at June 30, 2026 (in thousands) (Note 12)	1,906,616	1,821,530
Common stock issuable (Note 18)	32,307
Accumulated deficit	(1,232,308)	(1,275,293)
Accumulated other comprehensive income	21
Total shareholders' equity	706,636	546,237
TOTAL LIABILITIES & SHAREHOLDERS' EQUITY	$ 992,106	$ 820,218

Value of common stock issuable at the end of the reporting period.

No definition available.

Name:	mux_CommonStockValueIssuable
Namespace Prefix:	mux_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Current portion of the liability for flow-through share premium. Flow-through shares (FTSs) may be issued by certain corporations in the mining, oil and gas, and renewable energy and energy conservation sectors may issue FTSs to help finance their exploration and project development activities. Flow-through shares must be newly issued shares that have the attributes generally attached to common shares.

+ References

No definition available.