v3.25.2
Financial Instruments Risk - Credit Risk Narrative (Details) - CAD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Disclosure of detailed information about borrowings [line items]    
Insurance coverage for company management $ 43.9 $ 38.8
Bottom of range    
Disclosure of detailed information about borrowings [line items]    
Payment terms 30 days  
Top of range    
Disclosure of detailed information about borrowings [line items]    
Payment terms 60 days  
Credit risk    
Disclosure of detailed information about borrowings [line items]    
Accounts receivables from non-government wholesale customers $ 26.2 22.8
Provision for expected credit losses 0.1 0.7
Credit risk | Provision for credit losses | Trade receivables    
Disclosure of detailed information about borrowings [line items]    
Financial assets 0.8 1.3
Write-off $ 0.1 $ 2.1
Credit risk | Trade receivables | One Customer    
Disclosure of detailed information about borrowings [line items]    
Concentration percentage (or more) 10.00%  
Credit risk | Trade receivables | Two Customers    
Disclosure of detailed information about borrowings [line items]    
Concentration percentage (or more)   10.00%