COMMITMENTS AND CONTINGENCIES (Details) (USD $)	3 Months Ended	1 Months Ended
Sep. 30, 2010	Oct. 31, 2011 Mt. Milligan RGLD Gold AG	Oct. 31, 2010 Mt. Milligan RGLD Gold AG	Oct. 20, 2010 Mt. Milligan RGLD Gold AG
Commitments and Contingencies
Percentage of payable gold right acquired				25.00%
Cash paid for acquisition of royalty interests	$ 25,000,000		$ 226,500,000
Maximum future additional payments upon satisfaction of certain conditions in the Purchase and Sale Agreement		71,300,000	85,000,000
Additional payments made		$ 13,700,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of cash payments made as a result of the contingent consideration arrangement related to the acquisition of royalty interests.

+ Details

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- Definition

Maximum amount of potential cash payments that could result from the contingent consideration arrangement related to the acquisition of royalty interests.

+ Details

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- Definition

The percentage of the payable gold produced for which the entity acquired the rights.

+ Details

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- Definition

The cash outflow from the purchase of royalty interests in mining properties is the amount of cash the mineral producer pays the owner of the mine or mineral resource.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15, 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-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

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585

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