Property, Plant and Equipment - Schedule of Components of Property, Plant and Equipment (Details) - CAD ($) $ in Thousands	Sep. 30, 2022	Mar. 31, 2022
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,076,350	$ 1,175,692
Less: Accumulated depreciation	(211,827)	(232,912)
Property, plant and equipment, net	864,523	942,780
Buildings and Greenhouses
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	733,399	766,931
Buildings and Greenhouses | Right-of-Use-Assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	85,144	89,228
Production and Warehouse Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	114,768	159,314
Production and Warehouse Equipment | Right-of-Use-Assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	27	55
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	65,545	69,304
Office and Lab Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	26,420	29,879
Computer Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	19,817	22,293
Land
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	17,515	18,917
Assets in Process
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 13,715	$ 19,771