INCOME AND MINING TAXES - Reconciliation of Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
INCOME AND MINING TAXES.
Loss before income and mining taxes	$ 67,036	$ (80,288)	$ (64,199)
Statutory tax rate (as a percent)	21.00%	21.00%	21.00%
US Federal and State tax recovery (expense) at statutory rate	$ 14,078	$ (16,860)	$ (13,482)
Reconciling items:
Equity loss / (income) from investments	15,310	(583)	1,326
Deconsolidation of McEwen Copper Inc.	(46,644)
Taxable gain on the disposal of McEwen Copper shares	6,179
Deferred tax liability on investment	38,340
Realized flow-through expenditures	3,570	2,169	6,148
Realized flow-through premium	821	(10)	(4,377)
Withholding tax	1,455	116
Adjustment for foreign tax rates	(629)	7,760	6,446
Permanent differences		8,072
Foreign exchange on translation of books	8,282	1,877	1,497
Losses expired	(42)	(4,308)	2,720
Proceeds received from sale of NSR	9,909	9,353	4,371
Adjustments in relation to prior years	(13,769)	(8,384)	(3,039)
Current and deferred mining tax liabilities	(632)
Movement in valuation allowance	(3,423)	(2,011)	(3,486)
Other	(294)
Income and mining tax expense (recovery)	$ 33,859	$ 5,806	$ (7,315)