Fair Value of Financial Instruments - Summary of Financial Assets and Liabilities Measured at Estimated Fair Value on a Recurring Basis (Details) - Fair Value Measurements Recurring - CAD ($) $ in Thousands	Sep. 30, 2022	Mar. 31, 2022
Assets:
Short-term investments	$ 396,702	$ 595,651
Restricted short-term investments	12,352	12,216
Other financial assets	613,058	788,306
Liabilities:
Unsecured senior notes	321,128	563,958
Derivative liability	691
Other liabilities	45,926	70,066
Acreage
Liabilities:
Derivative liability		47,000
Warrant
Liabilities:
Derivative liability		26,920
Level 1
Assets:
Short-term investments	396,702	595,651
Restricted short-term investments	12,352	12,216
Other financial assets	312	490
Level 2
Liabilities:
Unsecured senior notes	321,128	563,958
Level 3
Assets:
Other financial assets	612,746	787,816
Liabilities:
Derivative liability	691
Other liabilities	$ 45,926	70,066
Level 3 | Acreage
Liabilities:
Derivative liability		47,000
Level 3 | Warrant
Liabilities:
Derivative liability		$ 26,920