RELATED PARTY (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2011 stakeholders ounces	Jun. 30, 2011 ounces
Related party
Maximum period of days gold inventory allocated to Royal Gold in an in-kind distribution will be held before sale (in days)	5
Crescent Valley Partners, L.P.
Related party
Percentage of royalty interests acquired (as a percent)	1.25%
General partner ownership percentage held by Denver Mining Finance Company (as a percent)	2.00%
Limited partner ownership percentage held by Royal Gold (as a percent)	29.60%
Board of director members holding limited partner interests (number of)	1
Aggregate percentage of limited partner interests held by certain Royal Gold's executives (as a percent)	35.56%
Quantity of gold inventories (in ounces)	12,735	15,255
Carrying value of the gold in inventory	$ 6.9	$ 8.1
Fair value of the gold in inventory	$ 20.6	$ 23.0

Percentage of limited partner ownership interest held by executives of a related party entity to the limited partnership.

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- Definition

Number of other member of board of directors holding limited partner interest other than the chairman of the board of directors and the chairman of the audit committee.

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- Definition

Fair value of the gold in inventory held by a third party refinery for the account of a related party of the Company.

+ Details

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- Definition

Quantity of gold inventories held by a third party refinery for the account of a related party of the Company.

+ Details

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- Definition

Maximum number of days, from the date of receipt, gold inventory received as a limited partner in-kind distribution will be sold.

+ Details

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- Definition

The net value royalty interest percentage owned as of the reporting date by a related party of the reporting entity.

+ Details

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- Definition

The number of units or percentage investment held by the managing member or general partner of the LLC or LP.

+ References

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

-Publisher AICPA

-Name Practice Bulletin (PB)

-Number 14

-Paragraph 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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- Definition

Carrying amount as of the balance sheet date of merchandise or materials to which the entity holds the title, but which are physically at another entity's facilities (for example work in process may be temporarily at the site of a subcontractor).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 3

-Section A

-Paragraph 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

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

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- Definition

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.

+ Details

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