v3.26.1
INTANGIBLE ASSETS - Intangible Assets Reconciliation (Details) - CAD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start $ 3,871.0 $ 3,271.9
Business combinations (Note 2 and 6)   475.4
Amortization (157.6) (132.5)
Impairment (31.9) (2.1)
Transfers and others (5.6) (5.2)
Foreign currency exchange differences (63.0) 169.2
Intangible assets, end 3,692.2 3,871.0
Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 5,506.2  
Intangible assets, end 5,457.2 5,506.2
Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (1,635.2)  
Intangible assets, end (1,765.0) (1,635.2)
Goodwill    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 2,439.7 1,971.3
Business combinations (Note 2 and 6)   350.2
Impairment 0.0 0.0
Transfers and others 0.0 0.0
Foreign currency exchange differences (39.9) 118.2
Intangible assets, end 2,399.8 2,439.7
Goodwill | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 3,040.3  
Intangible assets, end 2,983.5 3,040.3
Goodwill | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (600.6)  
Intangible assets, end (583.7) (600.6)
Capitalized development costs    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 320.3 287.2
Business combinations (Note 2 and 6)   0.7
Amortization (49.7) (35.8)
Impairment (31.4) (2.1)
Transfers and others (8.3) (0.5)
Foreign currency exchange differences (2.5) 3.8
Intangible assets, end 290.7 320.3
Capitalized development costs | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 599.1  
Intangible assets, end 618.2 599.1
Capitalized development costs | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (278.8)  
Intangible assets, end (327.5) (278.8)
Customer relationships    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 617.7 505.2
Business combinations (Note 2 and 6)   124.5
Amortization (49.9) (44.5)
Impairment 0.0 0.0
Transfers and others 0.0 0.0
Foreign currency exchange differences (13.4) 32.5
Intangible assets, end 554.4 617.7
Customer relationships | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 955.6  
Intangible assets, end 940.8 955.6
Customer relationships | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (337.9)  
Intangible assets, end (386.4) (337.9)
Licenses    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 235.4 246.3
Business combinations (Note 2 and 6)   0.0
Amortization (17.3) (17.2)
Impairment 0.0 0.0
Transfers and others 0.0 0.0
Foreign currency exchange differences (2.7) 5.1
Intangible assets, end 216.4 235.4
Licenses | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 337.4  
Intangible assets, end 334.7 337.4
Licenses | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (102.0)  
Intangible assets, end (118.3) (102.0)
Technology, software and ERP    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 243.5 253.4
Business combinations (Note 2 and 6)   0.0
Amortization (38.5) (33.8)
Impairment (0.5) 0.0
Transfers and others 2.3 (4.8)
Foreign currency exchange differences (4.7) 9.1
Intangible assets, end 212.5 243.5
Technology, software and ERP | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 528.6  
Intangible assets, end 527.5 528.6
Technology, software and ERP | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (285.1)  
Intangible assets, end (315.0) (285.1)
Other intangible assets    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 14.4 8.5
Business combinations (Note 2 and 6)   0.0
Amortization (2.2) (1.2)
Impairment 0.0 0.0
Transfers and others 0.4 0.1
Foreign currency exchange differences 0.2 0.5
Intangible assets, end 18.4 14.4
Other intangible assets | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start 45.2  
Intangible assets, end 52.5 45.2
Other intangible assets | Accumulated amortization and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets, start (30.8)  
Intangible assets, end (34.1) (30.8)
Additions – internal development    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 72.7 86.6
Additions – internal development | Capitalized development costs    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 62.3 67.0
Additions – internal development | Customer relationships    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – internal development | Licenses    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – internal development | Technology, software and ERP    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 10.4 19.6
Additions – internal development | Other intangible assets    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – acquired separately    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 1.0 1.3
Additions – acquired separately | Capitalized development costs    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – acquired separately | Customer relationships    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – acquired separately | Licenses    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 1.0 1.2
Additions – acquired separately | Technology, software and ERP    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – acquired separately | Other intangible assets    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.1
Additions – non cash    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 5.6 6.4
Additions – non cash | Capitalized development costs    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – non cash | Customer relationships    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – non cash | Licenses    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – non cash | Technology, software and ERP    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions 0.0 0.0
Additions – non cash | Other intangible assets    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Additions $ 5.6 $ 6.4