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Note 1 - Organization and Business (Details Textual) $ in Thousands, shares in Millions				1 Months Ended	3 Months Ended	9 Months Ended
	Nov. 10, 2017 a	Sep. 29, 2014	Nov. 29, 2010 USD ($) a shares	Sep. 30, 2012 a	Mar. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jan. 18, 2019	Jan. 08, 2015 USD ($)
Number of Wholly Owned Subsidiaries					2	2
Long-term Debt, Total					$ 0	$ 0
The Joint Venture Company [Member]
Exploration Budget					$ 6,700
Equity Method Investment, Ownership Percentage					60.00%	60.00%
Royal Gold [Member] | The Joint Venture Company [Member]
Initial Investment to Fund Exploration Activity								$ 5,000
Percentage of Economic Interest That May Be Obtained								40.00%
Amount of Economic Interest That May Be Obtained								$ 30,000
Payments to Acquire Interest in Joint Venture						$ 33,000
Percentage Ownership in Company					40.00%	40.00%
CORE Alaska [Member]
Percent Membership Interest, Contingent Sale, Percent							20.00%
Unpatented Mining Claims from the State of Alaska for Gold and Minerals [Member]
Acreage of Unpatented Mining Claims | a			18,021
Unpatented State of Alaska Mining Claims [Member] | The Joint Venture Company [Member]
Number of Mining Claims Acquired	541
Mining Claims Acquired, Area | a	84,840
Production Royalty Percentage	3.00%
Native Village of Tetlin Land [Member]
Percentage of Leasehold Interest			100.00%
Leasehold Interest Acreage | a			675,000
Contango [Member]
Parent Contribution			$ 3,500
Sale of Stock, Number of Shares Issued in Transaction | shares			1.6
Royal Gold [Member]
Overriding Royalty Interest			3.00%
Royal Gold [Member] | The Tetlin Lease and Unpatented State of Alaska Mining Claims [Member] | JEX [Member]
Royalty Interest Sold		3.00%
Royal Gold [Member] | Unpatented State of Alaska Mining Claims [Member] | JEX [Member]
Royalty Interest Sold		2.00%
JEX [Member]
Overriding Royalty Interest				2.00%	3.00%	3.00%
JEX [Member] | Unpatented State of Alaska Mining Claims [Member]
Number of Mining Claims Acquired				474
Mining Claims Acquired, Area | a				71,896
Production Royalty Percentage				2.00%

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