The cash contribution to be made to obtain membership rights in joint venture.

No definition available.

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- Definition

Maximum purchase price for each payable ounce of gold.

+ References

No definition available.

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- Definition

The aggregate fair value as of the reporting date of noncontrolling interests.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of membership interest that the company has the right to obtain in joint venture.

+ References

No definition available.

+ Details

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- Definition

Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

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Balance Type:	debit
Period Type:	instant

- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26805-111562

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Period Type:	duration

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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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=98514028&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

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- Details

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- Details

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Data Type:	na
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- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=rgld_PeakGoldJointVentureMember
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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENTLY ISSUED AND RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS (Details) $ in Thousands	12 Months Ended
	Jun. 30, 2018 USD ($) $ / oz	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Oct. 20, 2016 $ / oz
Available-for-sale securities	$ 19,100	$ 3,700
Realized gain on available-for-sale security			$ 2,340
Minimum
Term of the contract	10 days
Maximum
Term of the contract	3 months
Mount Milligan
Cash payment for each ounce of gold (in dollars per ounce) \| $ / oz	435			435
Peak Gold
Fair value of the company	$ 45,700
Membership interest	40.00%
Cash contribution	$ 30,000
Membership interest	40.00%	29.50%
Cash contribution	$ 30,000	$ 18,000