SEGMENTED INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
SEGMENTED INFORMATION
Gold and silver sales	$ 10,459		$ 23,957
Loss on investment in Minera Santa Cruz S.A., (net of amortization)	(1,551)	679	(1,788)	3,728
Production costs applicable to sales	8,278		18,871
Mine development and operating costs	98	3,494	569	6,216
Mine construction costs		6,994		8,635
Exploration costs	4,889	10,073	19,489	21,857
Impairment of investment in MSC	95,878		95,878
Impairment of mineral property interests and property and equipment	27,729	179	27,729	179
Loss (gain) on sale of assets	6,791	(128)	6,791	(130)
Operating loss	(139,654)	(24,859)	(158,021)	(45,983)
Investment in Minera Santa Cruz S.A.	176,282		176,282		273,948
Mineral property interests	731,449		731,449		767,067
Total assets	982,371		982,371		1,150,937
Argentina
SEGMENTED INFORMATION
Loss on investment in Minera Santa Cruz S.A., (net of amortization)	(1,551)	679	(1,788)	3,728
Exploration costs	2,017	5,025	13,479	9,830
Impairment of investment in MSC	95,878		95,878
Impairment of mineral property interests and property and equipment	27,729		27,729
Loss (gain) on sale of assets	326		326
Operating loss	(129,703)	(5,266)	(141,615)	(7,689)
Investment in Minera Santa Cruz S.A.	176,282		176,282		273,948
Mineral property interests	511,363		511,363		539,092
Total assets	691,504		691,504		825,047
Mexico
SEGMENTED INFORMATION
Gold and silver sales	10,459		23,957
Production costs applicable to sales	8,278		18,871
Mine development and operating costs	98	3,494	569	6,216
Mine construction costs		6,994		8,635
Exploration costs	1,949	3,792	4,434	8,547
Operating loss	(970)	(15,268)	(3,020)	(26,083)
Mineral property interests	12,187		12,187		12,707
Total assets	48,799		48,799		47,359
United States
SEGMENTED INFORMATION
Exploration costs	870	1,092	1,450	2,906
Loss (gain) on sale of assets	6,468		6,468
Operating loss	(6,110)	(1,301)	(7,055)	(3,630)
Mineral property interests	207,899		207,899		215,268
Total assets	213,099		213,099		220,148
Corporate & Other
SEGMENTED INFORMATION
Exploration costs	53	164	126	574
Loss (gain) on sale of assets	(3)		(3)
Operating loss	(2,871)	(3,024)	(6,331)	(8,581)
Total assets	$ 28,969		$ 28,969		$ 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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Total costs related to goods produced and sold during the reporting period.

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Other costs incurred and are directly related to construction and development services.

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Aggregate revenue from the sale of minerals and related products, and from rendering services such as exploration, development, mining, processing and providing mining support activities.

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