v3.26.1
Asset Impairment and Restructuring Costs - Summary of Pre-tax Charges Recognized in Restructuring Actions and Other Impairments (Details) - CAD ($)
 3 Months Ended 12 Months Ended
Mar. 31, 2025
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Costs recorded in operating expenses:        
Impairment of property, plant and equipment, net   $ 1,715,000 $ 13,523,000  
(Gain) impairment of property, plant and equipment, net       $ (40,578,000)
Impairment of intangible assets   8,028,000   17,266,000
Impairment of goodwill $ 0 47,491,000   42,081,000
Contractual and other settlement obligations     (1,942,000) (2,129,000)
Employee-related, other asset impairment and other restructuring costs   9,845,000 19,652,000 49,347,000
Restructuring and share-based compensation       (14,500,000)
Other impairments       79,501,000
Total asset impairment and restructuring costs   67,079,000 31,233,000 65,987,000
Total restructuring, asset impairment and related costs   76,957,000 33,224,000 65,001,000
Property, Plant and Equipment        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges   1,715,000 (13,523,000) 40,578,000
Intangible Assets        
Costs recorded in operating expenses:        
Asset impairment and restructuring costs   8,028,000 0 17,266,000
Costs Recorded in Cost of Goods Sold        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges   $ 9,878,000 $ 1,991,000 (986,000)
Costs recorded in operating expenses:        
Total restructuring, asset impairment and related costs       (986,000)
Costs Recorded in Operating Expenses        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges       (13,514,000)
Costs recorded in operating expenses:        
Asset impairment and restructuring costs       79,501,000
Costs Recorded in Operating Expenses | Property, Plant and Equipment        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges       (40,578,000)
Costs Recorded in Operating Expenses | Intangible Assets        
Costs recorded in operating expenses:        
Asset impairment and restructuring costs       17,266,000
Costs Recorded in Operating Expenses | Goodwill        
Costs recorded in operating expenses:        
Asset impairment and restructuring costs       42,081,000
Costs Recorded in Operating Expenses | Contractual And Other Settlement Obligations        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges       (2,129,000)
Costs Recorded in Operating Expenses | Employee-related and Other Restructuring Costs        
Restructuring Cost And Reserve [Line Items]        
Restructuring and other charges       29,193,000
Costs recorded in operating expenses:        
Asset impairment and restructuring costs       $ 20,154,000