Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Revenue		$ 188,404	$ 202,117
COSTS AND EXPENSES
Amortization		26,433	29,937
General and administrative		10,272	11,554
Pre-development, reclamation, and other		11,412	13,712
Total costs and expenses		186,802	173,016
OTHER INCOME (EXPENSE), NET
Loss on debt extinguishments		0	(9,173)
Fair value adjustments, net, pretax		10,605	(3,799)
Interest expense, net of capitalized interest		(4,568)	(4,910)
Other, net		1,737	3,627
Total other income (expense), net		7,774	(14,255)
Income (loss) before income and mining taxes		9,376	14,846
Income and mining tax (expense) benefit		(1,694)	(12,786)
NET INCOME (LOSS)		7,682	2,060
OTHER COMPREHENSIVE INCOME (LOSS), Net of Tax:
Unrealized gain (loss) on hedger, net of tax		(5,218)	27,357
Reclassification adjustments for realized (gain) loss on cash flow hedges		(460)	2,721
Other comprehensive income (loss)		(4,758)	24,636
COMPREHENSIVE INCOME (LOSS)		$ 2,924	$ 26,696
Basic EPS
Earnings Per Share, Basic		$ 0.03	$ 0.01
Diluted EPS
Earnings Per Share, Diluted		$ 0.03	$ 0.01
Accumulated Deficit [Member]
OTHER INCOME (EXPENSE), NET
NET INCOME (LOSS)		$ 7,682	$ 2,060
Product
COSTS AND EXPENSES
Costs applicable to sales	[1]	133,267	108,147
Mineral, Exploration
COSTS AND EXPENSES
Costs applicable to sales		$ 5,418	$ 9,666

[1] Excludes amortization.