Note 3 -Revision of Previously Issued Financial Statements for Immaterial Misstatements - Schedule of Prior Period Adjustments (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Total current assets	$ 267,727	$ 341,627
Properties, plants, equipment and mineral interests, net	2,569,790	2,310,810
Total assets	2,927,172	2,728,808	$ 2,700,210
Accrued taxes	4,030	12,306
Total current liabilities	178,466	160,383
Deferred tax liability	125,846	149,706
Total liabilities	948,205	968,021
Accumulated deficit	(403,931)	(353,651)
Total shareholders' equity	1,978,967	1,760,787	1,713,785	$ 1,696,534
Total liabilities and shareholders' equity	2,927,172	2,728,808
Cost of sales and other direct production costs	458,811	417,879	382,663
Depreciation, depletion and amortization	143,938	171,793	148,110
Total cost of sales	602,749	589,672	530,773
Gross profit	116,156	217,801	161,100
Income from operations	12,438	83,420	66,978
Loss before income and mining taxes	(44,914)	5,526	(1,258)
Income and mining tax benefit (provision)	7,566	29,569	(8,199)
Net (loss) income	(37,348)	35,095	(9,457)
Loss applicable to common shareholders	(37,900)	34,543	(10,009)
Comprehensive loss	$ (6,444)	$ 39,528	$ (5,036)
Basic (loss) income per common share after preferred dividends	$ 0.07	$ 0.06	$ (0.02)
Diluted (loss) income per common share after preferred dividends	$ 0.07	$ 0.06	$ (0.02)
Depreciation, depletion and amortization	$ 145,147	$ 172,651	$ 155,006
Cash provided by operating activities	$ 89,890	$ 220,337	$ 180,793