Note 3 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jul. 20, 2018
Deferred Tax Liabilities, Net, Total	$ 139,700		$ 139,700
Income Tax Expense (Benefit), Total	(1,614)	$ (2,679)	(20,009)	$ (1,484)
Klondex Mines Ltd [Member]
Deferred Tax Liabilities, Net, Total					$ 59,500
Income Tax Expense (Benefit), Total	2,400		10,300
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Deferred Tax Liabilities, Net, Total	43,100		43,100
Foreign Tax Authority [Member] | Canada Revenue Agency [Member]
Deferred Tax Liabilities, Net, Total	100,300		100,300
Foreign Tax Authority [Member] | Mexican Tax Authority [Member]
Deferred Tax Liabilities, Net, Total	$ 3,700		$ 3,700