INVESTMENT ASSETS, NET - Additional Information (Details)	3 Months Ended		6 Months Ended
	Oct. 31, 2021 USD ($) ft²	Oct. 31, 2020 USD ($)	Oct. 31, 2021 USD ($) ft²	Oct. 31, 2020 USD ($)	Apr. 30, 2021 ft²
Area of Land	143,000		143,000
Area of land sold	143,000		143,000
Depreciation on buildings | $	$ 98,000	$ 140,000	$ 201,000	$ 262,000
Warehouse and Office Buildings
Area of Land					143,000
Area of land sold	143,000		143,000
Florida | Warehouse and Office Buildings
Area of land sold	143,000		143,000