Income and Mining Taxes - Reconciliation of Effective Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income and mining tax (expense) benefit at statutory rate	$ (764)	$ (13,161)	$ 75,185
State tax provision from continuing operations	2,009	(152)	1,243
Change in valuation allowance	(28,615)	(17,522)	(77,220)
Percentage depletion	4,968	5,056	820
Uncertain tax positions	920	2,321	2,358
U.S. and foreign permanent differences	4,105	3,844	2,272
Foreign exchange rates	(384)	1,390	(7,066)
Foreign inflation and indexing	(1,087)	684	(2,933)
Foreign tax rate differences	(4,901)	(3,971)	19,729
Mining, foreign withholding, and other taxes	(12,599)	(17,457)	(2,746)
Other, net	1,390	1,923	(513)
Income and mining tax benefit (expense)	$ 34,958	$ 37,045	$ (11,129)