v3.26.1
PROPERTY, PLANT AND EQUIPMENT - Summaries of Property, Plant and Equipment (Details) - CAD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start $ 2,989.5 $ 2,515.6
Business combinations (Note 2)   135.5
Disposals (6.6) (12.6)
Depreciation (220.0) (204.8)
Impairment (9.3) (2.2)
Transfers and others (21.7) 23.9
Foreign currency exchange differences (26.7) 168.8
Property, plant and equipment, end 2,993.0 2,989.5
Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 287.8 356.2
Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   9.1
Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 4,688.7  
Property, plant and equipment, end 4,808.4 4,688.7
Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start (1,699.2)  
Property, plant and equipment, end (1,815.4) (1,699.2)
Buildings and land    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 523.4 387.0
Business combinations (Note 2)   72.1
Disposals 0.0 (0.2)
Depreciation (34.4) (30.1)
Impairment 0.0 (0.8)
Transfers and others 7.4 52.9
Foreign currency exchange differences (7.6) 23.7
Property, plant and equipment, end 508.0 523.4
Buildings and land | Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 19.2 18.8
Buildings and land | Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   0.0
Buildings and land | Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 842.5  
Property, plant and equipment, end 858.7 842.5
Buildings and land | Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start (319.1)  
Property, plant and equipment, end (350.7) (319.1)
Simulators    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 1,997.1 1,727.8
Business combinations (Note 2)   22.4
Disposals (0.2) 0.0
Depreciation (157.6) (148.2)
Impairment (9.3) (0.4)
Transfers and others 173.4 262.6
Foreign currency exchange differences (10.6) 128.2
Property, plant and equipment, end 2,014.8 1,997.1
Simulators | Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 22.0 4.7
Simulators | Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   0.0
Simulators | Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 3,158.7  
Property, plant and equipment, end 3,244.7 3,158.7
Simulators | Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start (1,161.6)  
Property, plant and equipment, end (1,229.9) (1,161.6)
Machinery and equipment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 64.2 61.6
Business combinations (Note 2)   4.3
Disposals (1.5) (0.2)
Depreciation (19.3) (20.2)
Impairment 0.0 (0.2)
Transfers and others 14.2 6.6
Foreign currency exchange differences (0.1) 2.4
Property, plant and equipment, end 70.4 64.2
Machinery and equipment | Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 12.9 9.9
Machinery and equipment | Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   0.0
Machinery and equipment | Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 241.6  
Property, plant and equipment, end 261.1 241.6
Machinery and equipment | Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start (177.4)  
Property, plant and equipment, end (190.7) (177.4)
Aircraft    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 88.3 79.6
Business combinations (Note 2)   0.0
Disposals (4.9) (12.1)
Depreciation (8.7) (6.3)
Impairment 0.0 (0.8)
Transfers and others 11.4 (3.8)
Foreign currency exchange differences (1.9) 5.1
Property, plant and equipment, end 98.0 88.3
Aircraft | Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 13.8 17.5
Aircraft | Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   9.1
Aircraft | Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 129.4  
Property, plant and equipment, end 142.1 129.4
Aircraft | Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start (41.1)  
Property, plant and equipment, end (44.1) (41.1)
Assets under construction    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 316.5 259.6
Business combinations (Note 2)   36.7
Disposals 0.0 (0.1)
Depreciation 0.0 0.0
Impairment 0.0 0.0
Transfers and others (228.1) (294.4)
Foreign currency exchange differences (6.5) 9.4
Property, plant and equipment, end 301.8 316.5
Assets under construction | Property, plant and equipment not subject to operating leases    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions 219.9 305.3
Assets under construction | Purchase of assets under lease (Note 15)    
Reconciliation of changes in property, plant and equipment [abstract]    
Additions   0.0
Assets under construction | Cost    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 316.5  
Property, plant and equipment, end 301.8 316.5
Assets under construction | Accumulated depreciation and impairment    
Reconciliation of changes in property, plant and equipment [abstract]    
Property, plant and equipment, start 0.0  
Property, plant and equipment, end $ 0.0 $ 0.0