Quarterly report pursuant to Section 13 or 15(d)

Mineral Properties - rollforward (Details)

v3.5.0.2
Mineral Properties - rollforward (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2016
Balance at beginning of period   $ 50,610
Increase in reclamation costs   150
Write-of of mineral properties (note 7) $ (62) (62)
Amortization   (1,468)
Balance at end of period 49,230 49,230
Lost Creek Property    
Balance at beginning of period   16,662
Increase in reclamation costs   338
Amortization   (1,468)
Balance at end of period 15,532 15,532
Other Us Properties [Member]    
Balance at beginning of period   13,210
Write-of of mineral properties (note 7)   (62)
Balance at end of period 13,148 13,148
Path Finder Mines [Member]    
Balance at beginning of period   20,738
Increase in reclamation costs   (188)
Balance at end of period $ 20,550 $ 20,550