Related Parties - Additional Information (Detail) - CAD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Disclosure of transactions between related parties [line items]
Payments of incremental benefit in the event of termination	$ 41	$ 19	$ 634
Related parties
Disclosure of transactions between related parties [line items]
Voting right percentage	58.70%
Related parties \| Top of range
Disclosure of transactions between related parties [line items]
Payments of incremental benefit in the event of termination	$ 4,633	$ 3,006	$ 2,484

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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