ASSET RETIREMENT OBLIGATIONS (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Asset retirement obligations
Cash bonding for mineral properties in the United States	$ 5,183,000		$ 5,183,000
Amortization of mineral property interests and asset retirement obligations	322,000	669,000
Changes in the asset retirement obligations
Asset retirement obligation liability, beginning balance	7,247,000	6,359,000	6,359,000
Settlements			(60,000)
Accretion of liability	101,000	113,000	461,000
Adjustment reflecting updated estimates			487,000
Asset retirement obligation liability, ending balance	7,348,000		7,247,000
Current portion of the asset retirement obligation	1,454,000		1,392,000
Tonkin property and El Gallo 1 mine portion of the El Gallo Complex
Asset retirement obligations
Number of most significant properties subject to reclamation obligations	2
Tonkin Complex
Asset retirement obligations
Undiscounted estimated reclamation costs	2,800,000
El Gallo 1 mine
Asset retirement obligations
Undiscounted estimated reclamation costs	4,600,000
Amortization of mineral property interests and asset retirement obligations	300,000	1,200,000
Amortization of capitalized asset retirement costs	$ 100,000

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

+ 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

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

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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-Publisher FASB

-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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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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- Definition

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.

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