REVENUES - Additional Information (Details)	3 Months Ended		9 Months Ended
	Jan. 31, 2023 USD ($) a customer	Jan. 31, 2022 USD ($) ft² customer	Jan. 31, 2023 USD ($) a customer	Jan. 31, 2022 USD ($) ft² customer
REVENUES
Number of customers | customer	2	2	3	3
Customer outstanding receivables	$ 0	$ 0	$ 0	$ 0
Revenues	$ 9,117,000	9,391,000	$ 35,975,000	35,404,000
Surface acres of land held | a	147		147
Customer A
REVENUES
Revenues	$ 1,025,000	1,458,000	$ 4,369,000	3,699,000
Customer B
REVENUES
Revenues	$ 3,778,000	$ 4,068,000	5,246,000	4,844,000
Customer C
REVENUES
Revenues			$ 7,763,000	$ 10,754,000
Warehouse and Office Buildings
REVENUES
Surface acres of land held | ft²		143,000		143,000
Warehouse and Office Buildings | Land sale revenue
REVENUES
Surface acres of land held | ft²		143,000		143,000