|
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 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||