SEGMENTED INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
SEGMENTED INFORMATION
Gold and silver sales	$ 11,778	$ 456	$ 35,735	$ 456
Income on investment in Minera Santa Cruz S.A. (net of amortization)	2,040	11,240	252	14,968
Production costs applicable to sales	7,907	119	26,778	119
Mine development and operating costs	747	2,406	1,316	8,622
Mine construction costs		4,671		13,306
Exploration costs	2,575	6,708	22,064	28,565
Impairment of investment in Minera Santa Cruz S.A.			95,878
Impairment of mineral property interests and property and equipment	6,287	2,902	34,016	3,081
Loss (gain) on sale of assets	(50)	(1,135)	6,741	(1,265)
Operating income (loss)	(8,845)	(10,625)	(166,866)	(56,608)
Investment in Minera Santa Cruz S.A.	177,080		177,080		273,948
Mineral property interests	724,841		724,841		767,067
Total assets	973,251		973,251		1,150,937
Argentina
SEGMENTED INFORMATION
Income on investment in Minera Santa Cruz S.A. (net of amortization)	2,040	11,240	252	14,968
Exploration costs	631	1,539	14,110	11,369
Impairment of investment in Minera Santa Cruz S.A.			95,878
Impairment of mineral property interests and property and equipment			27,729
Loss (gain) on sale of assets	(10)		316
Operating income (loss)	1,131	9,129	(139,297)	1,440
Investment in Minera Santa Cruz S.A.	177,080		177,080		273,948
Mineral property interests	511,363		511,363		539,092
Total assets	691,579		691,579		825,047
Mexico
SEGMENTED INFORMATION
Gold and silver sales	11,778	456	35,735	456
Production costs applicable to sales	7,907	119	26,778	119
Mine development and operating costs	747	2,406	1,316	8,622
Mine construction costs		4,671		13,306
Exploration costs	1,148	3,847	5,582	12,394
Operating income (loss)	393	(12,650)	(2,627)	(38,733)
Mineral property interests	12,093		12,093		12,707
Total assets	51,272		51,272		47,359
United States
SEGMENTED INFORMATION
Exploration costs	634	999	2,084	3,905
Impairment of mineral property interests and property and equipment	6,287		6,287
Loss (gain) on sale of assets	(40)		6,428
Operating income (loss)	(8,499)	(4,234)	(17,102)	(7,864)
Mineral property interests	201,385		201,385		215,268
Total assets	205,457		205,457		220,148
Corporate & Other
SEGMENTED INFORMATION
Exploration costs	162	323	288	897
Loss (gain) on sale of assets			(3)
Operating income (loss)	(1,870)	(2,870)	(7,840)	(11,451)
Total assets	$ 24,943		$ 24,943		$ 58,383

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Mineral properties, net of adjustments.

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