Represents the net impairment charge.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Represents the quantity of physical commodities produced by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of gain (loss) recognized on the sale of mineral property interests.

+ 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 amount of carrying value of the mineral property interests.

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No definition available.

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- Definition

Represents the tax rate on mining real estate property of the value of the economically viable reserves of mining projects.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Represents the price of mineral property interests under the sale agreement.

+ References

No definition available.

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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)

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-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

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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)

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-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)

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-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

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-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

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

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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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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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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

No definition available.

+ Details

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MINERAL PROPERTY INTERESTS AND ASSET RETIREMENT OBLIGATIONS (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended	9 Months Ended						3 Months Ended	9 Months Ended	0 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	13 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Argentina	Sep. 30, 2013 Telken Tenements	Sep. 30, 2013 Este Tenements	Sep. 30, 2013 Piramides Tenements	Sep. 30, 2013 Tobias Tenements	Sep. 30, 2012 Property, plant and equipment Argentina	Sep. 30, 2012 Other United States Properties Nevada	Sep. 30, 2012 Other United States Properties Nevada	May 31, 2013 Limo Complex	Sep. 30, 2013 Limo Complex	Sep. 30, 2013 El Gallo Complex	Sep. 30, 2013 El Gallo Complex	Sep. 30, 2013 El Gallo Complex Gold equivalents oz	Sep. 30, 2013 El Gallo Complex Gold equivalents oz	Dec. 31, 2012 El Gallo Complex Gold equivalents oz	Sep. 30, 2013 El Gallo Complex Gold equivalents oz	Sep. 30, 2013 Tonkin property and El Gallo 1 mine portion of the El Gallo Complex Item	Sep. 30, 2013 West Battle Mountain Complex	Sep. 30, 2013 West Battle Mountain Complex	Sep. 30, 2013 West Battle Mountain Complex Nevada	Sep. 30, 2013 West Battle Mountain Complex Nevada	Jun. 30, 2013 Exploration properties in Santa Cruz, Argentina	Sep. 30, 2013 Exploration properties in Santa Cruz, Argentina	Jun. 30, 2013 Exploration properties in Santa Cruz, Argentina MSC	Sep. 30, 2013 Tonkin Complex
Mineral Property Interests
Quantity produced (in ounces)																		8,027	23,370	6,949	30,319
Number of most significant properties subject to reclamation obligations																						2
Undiscounted estimated reclamation costs																$ 4,600,000	$ 4,600,000													$ 3,800,000
Cash bonding for mineral properties in the United States	5,183,000		5,183,000		5,183,000
Amortization of mineral property interests and asset retirement obligations			1,244,000													300,000	1,200,000
Price of mineral property interests under the sale agreement														800,000
Carrying value of mining claims														7,200,000									6,300,000	6,300,000
Loss on disposal														6,400,000	3,900,000
Tax on mining real estate property (as a percent)																											1.00%		1.00%
Impairment charges	6,287,000	2,902,000	34,016,000	3,081,000		27,729,000	13,792,000	2,784,000	5,079,000	6,074,000	179,000	2,902,000	2,902,000												6,287,000	6,287,000	27,700,000
Deferred income tax														2,500,000									2,200,000					2,300,000
Net impairment charge																							4,100,000	4,100,000				25,400,000
Changes in the asset retirement obligations
Asset retirement obligation liability - opening balance			6,359,000	6,253,000	6,253,000
Settlements			(56,000)		(47,000)
Accretion of liability	113,000	110,000	347,000	342,000	447,000
Adjustment reflecting updated estimates			(29,000)		(294,000)
Asset retirement obligation liability - ending balance	6,616,000		6,616,000		6,359,000
Current portion of the asset retirement obligation	$ 1,351,000		$ 1,351,000		$ 130,000