Represents the number of equity securities sold during the period.

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Represents the option to acquire a percentage of royalty pursuant to the agreement.

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No definition available.

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Represents percentage of net smelter return.

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The amount of cash inflow from sale of interests in joint venture and sale of equity securities.

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No definition available.

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

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Amount of gain (loss) on sale or disposal of an equity method investment.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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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No definition available.

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Mineral properties, net of adjustments.

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The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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No definition available.

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SALE OF PEAK GOLD JV INTEREST (Details) - USD ($) $ in Thousands			3 Months Ended	6 Months Ended
	Sep. 30, 2020	Sep. 29, 2020	Sep. 30, 2020	Dec. 31, 2020	Jun. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of Peak Gold JV interest				$ 49,154
Proceeds from sale of Contango shares				12,146
Total cash consideration	$ 61,300
Stream and royalty interests, net				2,231,980	$ 2,318,913
Gain on sale of Peak Gold JV interest				33,906
Peak Gold LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total cash consideration	$ 4,000
Percentage of royalty that can be acquired	50.00%
Peak Gold
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net smelter return (NSR) (as a percent)	28.00%
Stream and royalty interests, net				$ 4,400
Alaska mining claims
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net smelter return (NSR) (as a percent)	3.00%	2.00%
Percentage of royalty that can be acquired	1.00%
Peak Gold
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of ownership interest	40.00%		40.00%
Proceeds from sale of Peak Gold JV interest	$ 49,200
Gain on sale of Peak Gold JV interest			$ 33,900
Contango
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of shares sold	809,744		809,744
Proceeds from sale of Contango shares	$ 12,100
Mark-to-market increase on sale			$ 3,600