EMPLOYEE COMPENSATION - Narrative (Details) - CAD ($) $ in Millions	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disclosure of analysis of single amount of discontinued operations [line items]
Employee benefits expense	$ 1,855.1	$ 1,824.4
Discontinued operations
Disclosure of analysis of single amount of discontinued operations [line items]
Employee benefits expense		$ 48.5

The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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