Represents the amount of amortization expense related to the capitalized asset retirement costs.

No definition available.

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- Definition

Represents the amount of deferred income tax recovery on impairment of mineral properties.

+ References

No definition available.

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- Definition

Represents the amount of amortization expense related to the mineral property interests and capitalized asset retirement costs.

+ References

No definition available.

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- Definition

Represents the number of properties of the entity which are subject to reclamation obligations.

+ References

No definition available.

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- Definition

Represents the percentage of annual fees on the value of the surety bonds.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of upfront deposit on the value of the surety bonds.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Current portion of reclamation reserve to restore a mining or drilling site to the condition agreed upon within the mining or drilling contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6911-107765

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

-URI http://asc.fasb.org/extlink&oid=6505190

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

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Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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- Definition

The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

+ References

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MINERAL PROPERTY INTERSTS AND ASSET RETIREMENT OBLIGATIONS (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended	0 Months Ended	3 Months Ended		6 Months Ended				3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Subsequent Event [Member]	Jun. 30, 2014 Argentina Reportable Segment [Member]	Jun. 30, 2013 Argentina Reportable Segment [Member]	Jun. 30, 2014 Argentina Reportable Segment [Member]	Jun. 30, 2013 Argentina Reportable Segment [Member]	Jun. 30, 2014 Tonkin Complex And El Gallo One Mine Complex [Member] item	Jun. 30, 2014 Tonkin Complex [Member]	Jun. 30, 2014 El Gallo Complex [Member]	Jun. 30, 2014 El Gallo Complex [Member]	Jun. 30, 2013 Telken Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Telken Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Este Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Este Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Piramides Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Piramides Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Tobias Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Tobias Tenements [Member] Argentina Reportable Segment [Member]	Jun. 30, 2013 Exploration Properties Located In Santa Cruz Province Argentina [Member]	Jun. 30, 2013 Exploration Properties Located In Santa Cruz Province Argentina [Member]	Jun. 30, 2014 Los Azules Copper Project [Member]	Jun. 30, 2014 Los Azules Copper Project [Member]	Jun. 30, 2014 Los Azules Copper Project [Member] Argentina Reportable Segment [Member]	Jun. 30, 2014 Los Azules Copper Project [Member] Argentina Reportable Segment [Member]
Mineral Property Interests [Line Items]
Number of most significant properties subject to reclamation obligations											2
Undiscounted estimated reclamation costs												$ 2,700,000	$ 4,600,000	$ 4,600,000
Cash bonding for mineral properties in the United States	4,817,000		4,817,000		5,183,000
Reduction in cash bonding requirements			(367,000)
Percentage of annual fees on surety bonds						1.50%
Percentage of upfront deposit on surety bonds						10.00%
Amortization of mineral property interests and asset retirement obligations			626,000	956,000									300,000	600,000
Amortization of capitalized asset retirement costs													100,000	100,000
Impairment charges	120,398,000	27,729,000	120,398,000	27,729,000			120,398,000	27,729,000	120,398,000	27,729,000					13,792,000	13,792,000	2,784,000	2,784,000	5,079,000	5,079,000	6,074,000	6,074,000	27,700,000	27,700,000	120,400,000	120,398,000	120,398,000	120,398,000
Recovery of deferred income tax	22,500,000	4,800,000	22,500,000	4,800,000																			2,300,000	2,300,000	22,500,000	22,500,000
Changes in the asset retirement obligations
Asset retirement obligation liability, beginning balance			7,247,000	6,359,000	6,359,000
Settlements			(18,000)		(60,000)
Accretion of liability	108,000	121,000	209,000	234,000	461,000
Adjustment reflecting updated estimates			(42,000)		487,000
Asset retirement obligation liability, ending balance	7,396,000		7,396,000		7,247,000
Current portion of the asset retirement obligation	$ 1,455,000		$ 1,455,000		$ 1,392,000