Note 6 - Income and Mining Taxes - Schedule of Changes in Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Line Items]
Balance at beginning of year	$ (39,152)	$ (77,210)	$ (86,634)
Balance at end of year	(72,856)	(39,152)	(77,210)
Increase Due to Uncertainty of Recovery [Member]
Income Tax Disclosure [Line Items]
Valuation allowance, deferred tax asset	(13,256)	(20,304)	786
Decrease Related to Utilization and Expiration [Member]
Income Tax Disclosure [Line Items]
Valuation allowance, deferred tax asset	5,143	58,362	8,638
Klondex Mines Ltd [Member] | Business Acquisition [Member]
Income Tax Disclosure [Line Items]
Valuation allowance, deferred tax asset	$ 25,591	$ 0	$ 0