v3.25.4
Investments - Equity Investments at FVTOCI (Details)
$ in Millions, $ in Millions
12 Months Ended
Sep. 18, 2025
USD ($)
Sep. 18, 2025
CAD ($)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Discovery        
Investments        
Gain (loss) on changes in fair value $ 67.4      
Realized gain on disposal $ 67.4 $ 93.1    
FVTOCI        
Investments        
Balance at beginning     $ 324.8 $ 246.4
Cost of additions     76.1 103.2
Gain (loss) on changes in fair value     802.3 46.6
Proceeds of disposition     (127.1) (45.5)
Impact of foreign exchange     29.2 (25.9)
Balance at ending     1,105.3 324.8
Realized gain on disposal     87.1  
Realized loss on disposal       (2.1)
FVTOCI | G Mining Ventures        
Investments        
Balance at beginning     133.8 47.6
Cost of additions       47.1
Gain (loss) on changes in fair value     392.3 46.5
Impact of foreign exchange     13.5 (7.4)
Balance at ending     539.6 133.8
FVTOCI | Discovery        
Investments        
Cost of additions     49.4  
Gain (loss) on changes in fair value     351.6  
Proceeds of disposition     (84.4)  
Impact of foreign exchange     6.4  
Balance at ending     323.0  
Realized gain on disposal     67.4  
FVTOCI | Labrador Iron Ore Royalty Corporation ("LIORC")        
Investments        
Balance at beginning     127.3 152.7
Gain (loss) on changes in fair value     4.2 (13.0)
Impact of foreign exchange     6.5 (12.4)
Balance at ending     138.0 127.3
FVTOCI | Other        
Investments        
Balance at beginning     63.7 46.1
Cost of additions     26.7 56.1
Gain (loss) on changes in fair value     54.2 13.1
Proceeds of disposition     (42.7) (45.5)
Impact of foreign exchange     2.8 (6.1)
Balance at ending     104.7 63.7
Realized gain on disposal     $ 19.7  
Realized loss on disposal       $ (2.1)