SHAREHOLDERS' EQUITY (Details)					12 Months Ended
	Oct. 01, 2015 USD ($) shares	Aug. 17, 2015 $ / shares	Jun. 18, 2015 $ / shares	Jan. 24, 2012 USD ($)	Dec. 31, 2015 CAD / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares
Exchangeable shares converted into common stock | shares						4,300,000	3,700,000
Exchangeable, shares outstanding | shares					24,213,000	24,213,000	28,521,000
Common stock issued | shares					274,421,000	274,421,000	271,579,000
Shares of common stock issued upon exercise of stock options | shares						272,000	1,499,000	48,000
Weighted average exercise price of stock options (in dollars per share) | $ / shares						$ 1.29	$ 1.29	$ 1.97
Exercise of stock options | $							$ 1,932,000	$ 95,000
Proceed from exercised stock options | $							2,292,000	171,000
Shares issued for settlement of accounts payable | $						$ 443,000	1,004,000
Annual return of capital declared (in dollars per share) | $ / shares			$ 0.01
First semi-annual return of capital payable (in dollars per share) | $ / shares		$ 0.005
Return of capital distribution (note 10) | $						$ 1,503,000
Number of shares remaining under agreement | shares						319,640
Share repurchase program | $						$ 1,769,000
Period of time over which common stock can be repurchased	12 months
Share repurchase program (in shares) | shares						1,896,442
Agreement to Terminate TNR Gold Corp Back In Right
Shares issued to TNR Gold Corp's to terminate back-in-right | $							1,352,000
Exploration costs | $						$ (8,798,000)	(11,332,000)	$ (24,829,000)
Maximum
Share repurchase program | $	$ 15,000,000
Share repurchase program (in shares) | shares	15,000,000
TNR
Agreement to Terminate TNR Gold Corp Back In Right
Shares issued to terminate TNR Gold Corp's back-in right (in shares) | shares						850,000
Net smelter return (as a percent)						0.40%
Exploration costs | $							$ (1,400,000)
Minera Andes
Shares of common stock issued upon exercise of stock options | shares						198,000
Weighted average exercise price of stock options (in dollars per share) | CAD / shares					CAD 1.96
Proceed from exercised stock options | $				$ 0.4
Proceeds from issuance of new shares, net of expenses | $						$ 400,000
Common Stock
Shares of common stock issued upon exercise of stock options | shares							1,499,000	48,000
Exercise of stock options | $							$ 1,932,000	$ 95,000
Shares issued for settlement of accounts payable (in shares) | shares						430,000	394,000
Share repurchase program | $						$ 1,769,000
Share repurchase program (in shares) | shares						1,896,000
Shares of common stock issued as payment for mining concessions in Mexico | shares								41,000
Agreement to Terminate TNR Gold Corp Back In Right
Shares issued to terminate TNR Gold Corp's back-in right (in shares) | shares							850,000
Shares issued to TNR Gold Corp's to terminate back-in-right | $							$ 1,352,000