XML 72 R41.htm IDEA: XBRL DOCUMENT v3.20.4
Note 5 - Environmental and Reclamation Activities (Details Textual)
$ in Thousands, $ in Millions
3 Months Ended 12 Months Ended
Dec. 31, 2020
USD ($)
Dec. 31, 2020
CAD ($)
Jun. 30, 2020
USD ($)
Dec. 31, 2019
USD ($)
Dec. 31, 2019
CAD ($)
Dec. 31, 2020
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Accrual for Environmental Loss Contingencies, Ending Balance $ 116,048     $ 108,374   $ 116,048 $ 108,389 $ 86,045
Asset Retirement Obligation, Liabilities Incurred 1,500              
Casa Berardi [Member]                
Asset Retirement Obligation, Revision of Estimate Before Discounting   $ 29.1     $ 15.7      
Asset Retirement Obligation, Liabilities Incurred 6,700              
Lucky Friday [Member]                
Asset Retirement Obligation, Revision of Estimate Before Discounting 36,900     34,300        
San Sebastian [Member]                
Asset Retirement Obligation, Revision of Estimate Before Discounting 600              
Asset Retirement Obligation, Liabilities Incurred $ 600              
Greens Creek [Member]                
Asset Retirement Obligation, Revision of Estimate Before Discounting     $ 107,700 $ 114,900        
Asset Retirement Obligation, Liabilities Incurred     $ 5,100          
Minimum [Member]                
Inflation Rate, Asset Retirement Obligation           2.00%    
Minimum [Member] | Reclamation and Abandonment Costs [Member] | Measurement Input, Risk Free Interest Rate [Member]                
Derivative Liability, Measurement Input 0.0575         0.0575    
Minimum [Member] | Asset Retirement Obligation [Member] | Measurement Input, Risk Free Interest Rate [Member]                
Derivative Liability, Measurement Input 0.0275         0.0275    
Maximum [Member]                
Inflation Rate, Asset Retirement Obligation           4.00%    
Maximum [Member] | Reclamation and Abandonment Costs [Member] | Measurement Input, Risk Free Interest Rate [Member]                
Derivative Liability, Measurement Input 0.145         0.145    
Maximum [Member] | Asset Retirement Obligation [Member] | Measurement Input, Risk Free Interest Rate [Member]                
Derivative Liability, Measurement Input 0.075         0.075