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Investments (Details) $ / shares in Units, $ in Thousands, item in Millions			3 Months Ended		6 Months Ended		12 Months Ended
	May 06, 2026 USD ($)	Feb. 21, 2023 item shares	Jun. 30, 2026 USD ($) $ / shares shares	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) $ / shares shares	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) shares	May 29, 2026	Dec. 31, 2024 shares
Investments
Percentage of contribution to gross royalty		2.00%
Contingent value rights issued \| item		5
Conversion of restricted share units (in shares) \| shares		5,000,000
Dilution gain			$ 18,469		$ 23,071
Return of capital					$ 152	$ 346
Restricted Stock Units ("RSUs")
Investments
Restricted share units outstanding \| shares			46,236,898		46,236,898		48,322,148		34,312,655
The Metals Royalty Company
Investments
Percentage of gross overriding production royalty interest acquired	1.00%
Percentage of additional royalty interest acquired	1.00%							1.00%
Royalty acquisition consideration transferred	$ 132,500
Royalty acquisition consideration transferred cash	125,000
Royalty acquisition consideration transferred shares	$ 7,500
Number of new shares issued in connection with finance offerings \| shares			6,983,616		11,118,097
The Metals Royalty Company \| Employee stock option
Investments
Stock options outstanding \| shares			872,250		872,250
The Metals Royalty Company \| Restricted Stock Units ("RSUs")
Investments
Restricted share units outstanding \| shares			4,569,000		4,569,000
The Metals Royalty Company
Investments
Number of shares acquired in connection with the finance offering \| shares					76,923
Value of shares acquired in connection with the finance offering					$ 1,000
Dilution gain			$ 18,500		$ 23,071		$ 5,649
Percentage of ownership			22.40%		22.40%		27.20%
Equity-accounted investment gain (loss)			$ (1,600)	$ (89)	$ (4,276)	$ (54,000)	$ 287
Return of capital							$ 346
1554997 B.C. Ltd
Investments
Percentage of ownership			27.20%		27.20%		27.20%
Equity-accounted investment gain (loss)			$ 32		$ (248)
Return of capital			$ 200		$ 152		$ 346
Declared and remitted return of capital per share \| $ / shares			$ 0.011		$ 0.011