SUBSEQUENT EVENT (Details) (Subsequent Events, Peak Gold, Tetlin, USD $) In Millions, unless otherwise specified	0 Months Ended
Jan. 08, 2015
Royal Alaska
Subsequent event
Payments to Acquire Interest in Joint Venture	$ 5.0
Royal Alaska \| Maximum
Subsequent event
Percentage of membership interest that can be obtained	40.00%
Amount that can be contributed to purchase membership interest	$ 30.0
Contango
Subsequent event
Membership interest controlled	100.00%

Represents the right of the contributed amount to purchase membership interest pursuant to the joint venture agreement.

No definition available.

Name:	rgld_JointVentureAgreementRightToObtainMembershipInterestContributions
Namespace Prefix:	rgld_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the right to obtain membership rights pursuant to the joint venture agreement.

+ References

No definition available.

+ Details

Name:	rgld_JointVentureAgreementRightToObtainMembershipInterestPercentage
Namespace Prefix:	rgld_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of membership interest controlled.

+ References

No definition available.

+ Details

Name:	rgld_MembershipInterestPercentageControlled
Namespace Prefix:	rgld_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

Reference 1: 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=31042434&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireInterestInJointVenture
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration