Liquidity (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Jun. 26, 2019	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash and cash equivalents				$ 4,593	$ 3,293	$ 3,250
Other exploration and property holding costs				11,400
Exploration expenditures				4,109	3,909
Shutdown and care and maintenance costs				1,797	1,889
General and administrative expenses				3,614	3,355
Increase in cash inflows				12,700
Reduction in working capital				400
Net operating margin				3,300
Net proceeds from the sale of the Company’s common stock				2,476	809
Remaining deposits payable				1,251
Income tax payments due				292	267
Cash Resources				9,300
Payments to acquire property				38	152
Subsequent Event [Member]
Net proceeds from the sale of the Company’s common stock			$ 400
Forecast
Reduction in working capital			500
Project expenditures			10,900
Forecast | Canada
Income tax payments due			300
Penoles
Other exploration and property holding costs				3,000
Velardena properties
Shutdown and care and maintenance costs				1,700	$ 1,900
Oxide Plant
Net operating margin				5,300
El Quevar Project
Maintenance and property holding costs				2,000
Payments to acquire property				1,000
El Quevar Project | Forecast
Maintenance and property holding costs			800
LPC Program
Other exploration and property holding costs				600
LPC Program | Forecast
General and administrative expenses			3,200
Santa Maria property | Forecast
Sale of an investment		$ 1,000
Sand Canyon [Member] | Forecast
Other exploration and property holding costs			3,000
Agreement
Remaining deposits payable				1,300
IPO
Net proceeds from the sale of the Company’s common stock				1,900
Golden Tag
Sale of miscellaneous assets				100
Sale of an investment				100
Electrum | Velardena properties | Forecast
Shutdown and care and maintenance costs			1,800
Autlan
Deposits received				$ 1,300
Autlan | Forecast
Remaining deposits payable			$ 1,300
Autlan | Agreement
Payments to acquire property	$ 1,500