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MINERAL PROPERTY INTERESTS AND ASSET RETIREMENT OBLIGATIONS (Details) (USD $)	12 Months Ended																				12 Months Ended	0 Months Ended	12 Months Ended			12 Months Ended		3 Months Ended			12 Months Ended	3 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended																									12 Months Ended	0 Months Ended	12 Months Ended					12 Months Ended					12 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 MSC	Dec. 31, 2013 Argentina	Dec. 31, 2012 Argentina	Dec. 31, 2013 Mexico	Dec. 31, 2012 Mexico	Dec. 31, 2011 Mexico	Dec. 31, 2013 Telken Tenements Argentina	Dec. 31, 2013 Este Tenements Argentina	Dec. 31, 2013 Piramides Tenements Argentina	Dec. 31, 2013 Tobias Tenements Argentina	Dec. 31, 2012 Property, plant and equipment Argentina	Dec. 31, 2013 Other United States Properties	Dec. 31, 2012 Other United States Properties	Dec. 31, 2013 Other United States Properties Nevada	Dec. 31, 2012 Other United States Properties Nevada	Dec. 31, 2013 Limo Complex	Dec. 31, 2012 Limo Complex	Dec. 31, 2013 Limo Complex Nevada	May 31, 2013 Limo Complex Sale agreement	Dec. 31, 2013 Limo Complex Sale agreement	Dec. 31, 2013 El Gallo 1 mine	Dec. 31, 2012 El Gallo 1 mine	Dec. 31, 2013 El Gallo 1 mine Gold equivalents oz	Dec. 31, 2013 Tonkin property and El Gallo 1 mine portion of the El Gallo Complex Item	Sep. 30, 2013 West Battle Mountain Complex	Dec. 31, 2013 West Battle Mountain Complex	Dec. 31, 2012 West Battle Mountain Complex	Dec. 31, 2013 West Battle Mountain Complex Nevada	Jun. 30, 2013 Exploration properties in Santa Cruz, Argentina	Dec. 31, 2013 Exploration properties in Santa Cruz, Argentina	Oct. 31, 2013 Exploration properties in Santa Cruz, Argentina Vend-in agreement MSC	Dec. 31, 2013 Mexico property interests	Dec. 31, 2013 Other Argentina exploration properties in San Juan, Argentina	Dec. 31, 2012 Other Argentina exploration properties in San Juan, Argentina	Dec. 31, 2013 Cerro Mojon Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Cerro Mojon Tenements in Santa Cruz, Argentina	Dec. 31, 2013 Los Azules Copper Project	Dec. 31, 2012 Los Azules Copper Project	Dec. 31, 2012 Telken Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Este Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Piramides Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Tobias Tenements in Santa Cruz, Argentina	Dec. 31, 2013 La Merced Tenements in Santa Cruz, Argentina	Dec. 31, 2012 La Merced Tenements in Santa Cruz, Argentina	Dec. 31, 2013 Cabeza de Vaca Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Cabeza de Vaca Tenements in Santa Cruz, Argentina	Dec. 31, 2013 El Trumai Tenements in Santa Cruz, Argentina	Dec. 31, 2012 El Trumai Tenements in Santa Cruz, Argentina	Dec. 31, 2013 Martes 13 Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Martes 13 Tenements in Santa Cruz, Argentina	Dec. 31, 2013 Celestina Tenements in Santa Cruz, Argentina	Dec. 31, 2012 Celestina Tenements in Santa Cruz, Argentina	Dec. 31, 2013 Other Argentina exploration properties in Santa Cruz, Argentina	Dec. 31, 2012 Other Argentina exploration properties in Santa Cruz, Argentina	Dec. 31, 2013 North Battle Mountain Complex in Nevada, United States	Dec. 31, 2012 North Battle Mountain Complex in Nevada, United States	Dec. 31, 2012 North Battle Mountain Complex in Nevada, United States Nevada	Nov. 30, 2012 North Battle Mountain Complex in Nevada, United States Option agreement	Dec. 31, 2012 North Battle Mountain Complex in Nevada, United States Option agreement	Dec. 31, 2013 East Battle Mountain Complex in Nevada, United States	Dec. 31, 2012 East Battle Mountain Complex in Nevada, United States	Dec. 31, 2013 Tonkin Complex	Dec. 31, 2012 Tonkin Complex	Dec. 31, 2013 Tonkin Complex Asset retirement obligation	Dec. 31, 2012 Tonkin Complex Asset retirement obligation	Dec. 31, 2011 Tonkin Complex Asset retirement obligation	Dec. 31, 2013 Gold Bar Complex	Dec. 31, 2012 Gold Bar Complex	Dec. 31, 2013 El Gallo in Mexico Asset retirement obligation	Dec. 31, 2012 El Gallo in Mexico Asset retirement obligation	Dec. 31, 2011 El Gallo in Mexico Asset retirement obligation	Dec. 31, 2012 El Gallo 2 Properties	Dec. 31, 2013 El Gallo 2 Properties	Dec. 31, 2012 El Gallo 2 Properties Mexico	Dec. 31, 2013 Limo Complex and Other United States Properties
Mineral Property Interests
Quantity produced (in ounces)																										31,129
Number of most significant properties subject to reclamation obligations																											2
Undiscounted estimated reclamation costs																								$ 4,600,000																																									$ 2,800,000
Cash bonding for mineral properties in the United States	5,183,000	5,183,000
Amortization of mineral property interests and asset retirement obligations	1,530,000																							1,500,000
Price of mineral property interests under the sale agreement																						800,000
Carrying value of mineral property interest	642,968,000	767,067,000	245,454,000		458,203,000	539,092,000	11,984,000	12,707,000	12,750,000						9,610,000	19,107,000			23,438,000	50,098,000		7,200,000		8,502,000	8,126,000			6,300,000	2,567,000	8,854,000				53,200,000		7,818,000	7,818,000	1,971,000	1,971,000	431,190,000	431,190,000	40,234,000	8,121,000	14,815,000	17,719,000	1,891,000	1,891,000	877,000	877,000	1,534,000	1,534,000	3,568,000	3,568,000	1,753,000	1,753,000	7,601,000	7,601,000	4,148,000	4,148,000				4,060,000	4,060,000	51,946,000	51,989,000				77,012,000	77,012,000				4,581,000	3,482,000
Loss on sale of assets, net of tax																							3,900,000
Loss (gain) on sale of assets	6,743,000	(1,110,000)	(36,000)		316,000																		6,400,000											0
Impairment charges	62,963,000	18,468,000		95,878,000	27,729,000	179,000		1,343,000		13,792,000	2,784,000	5,079,000	6,074,000	179,000	9,497,000	2,900,000	9,497,000	2,902,000	19,450,000		19,450,000							6,300,000			6,287,000	27,700,000																												14,044,000		14,000,000													1,300,000		1,343,000	28,900,000
Recovery of deferred income tax																							2,500,000					2,200,000					2,300,000																																													10,100,000
Net impairment charge																												4,100,000					25,400,000																																													18,800,000
Option to earn interest in property after incurring specified cumulative project related expenditures (as a percent)																																																													51.00%
Cumulative project related expenditures to be incurred to earn interest in property																																																													2,400,000
Mineral property interest, carrying value before impairment																2,900,000																																														18,200,000
Implied value of the option agreement																																																														4,200,000
Deferred tax liability related to mineral properties transferred																																		17,300,000
Exploration and related expenditure costs	24,829,000	47,179,000	42,983,000		14,776,000	25,091,000	6,658,000	15,918,000	29,160,000
Amortization of mineral property interests																																			1,000,000
Credit adjusted risk free rate (as a percent)																																																																			8.70%	8.70%	8.70%			6.40%	6.40%	6.40%
Inflation rate (as a percent)																																																																			3.00%	3.00%	3.00%			3.80%	3.80%	3.80%
Amortization of asset retirement obligations																																			500,000
Changes in the asset retirement obligations
Asset retirement obligation liability - opening balance	6,359,000	6,253,000
Settlements	(60,000)	(47,000)
Accretion of liability	461,000	447,000	524,000
Adjustment reflecting updated estimates	487,000	(294,000)
Asset retirement obligation liability - ending balance	7,247,000	6,359,000	6,253,000
Current portion of the asset retirement obligation	$ 1,392,000	$ 130,000

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