Note 7 - Income and Mining Taxes - Schedule of Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Computed “statutory” benefit (provision), Amount	$ (13,905)	$ 17,429	$ 9,432
Computed “statutory” benefit (provision), Percentage	22.00%	21.00%	21.00%
Percentage depletion, Amount	$ 9,895	$ 4,205	$ 8,542
Percentage depletion, Percentage	(15.00%)	5.00%	19.00%
Change in valuation allowance, Amount	$ (14,195)	$ (20,016)	$ (8,113)
Change in valuation allowance, Percentage	21.00%	(24.00%)	(18.00%)
State taxes, net of federal tax benefit, Amount	$ (4,823)	$ (2,731)	$ (158)
State taxes, net of federal tax benefit, Percentage	7.00%	(3.00%)	0.00%
Foreign currency remeasurement, Amount	$ 590	$ (4,155)	$ 4,559
Foreign currency remeasurement, Percentage	(1.00%)	(5.00%)	10.00%
Rate differential on foreign earnings, Amount	$ 3,293	$ 6,553	$ 1,515
Rate differential on foreign earnings, Percentage	(5.00%)	8.00%	3.00%
Compensation, Amount	$ (2,684)	$ (1,636)	$ 173
Compensation, Percentage	4.00%	(2.00%)	0.00%
Mining and other taxes, Amount	$ (7,661)	$ (1,359)	$ (6,609)
Mining and other taxes, Percentage	12.00%	(2.00%)	(15.00%)
Other, Amount	$ (924)	$ 488	$ (1,775)
Other, Percentage	1.00%	1.00%	(3.00%)
Total benefit (provision), Amount	$ (30,414)	$ (1,222)	$ 7,566
Total benefit (provision), Percentage	46.00%	(1.00%)	17.00%