INFORMATION ABOUT THE COMPANY'S OPERATIONS IN DIFFERENT INDUSTRY SEGMENTS (Details) - USD ($)	3 Months Ended		6 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Apr. 30, 2020
Segment Reporting Information [Line Items]
Revenues	$ 9,256,000	$ 3,960,000	$ 13,462,000	$ 8,727,000
Net income (loss)	798,000	(2,169,000)	1,391,000	(2,365,000)
Provision (benefit) for income taxes	319,000	(622,000)	465,000	(756,000)
Interest expense (income), net (b)	12,000	(141,000)	6,000	(265,000)
Depreciation	132,000	161,000	270,000	289,000
EBITDA (c)	1,261,000	(2,771,000)	2,132,000	(3,097,000)
Capital expenditures	3,000	5,000	3,000	5,000
TOTAL ASSETS	95,720,000	95,629,000	$ 95,720,000	95,629,000	$ 96,666,000
Number of business segment			1
Land Development
Segment Reporting Information [Line Items]
Revenues	8,989,000	3,620,000	$ 12,845,000	8,045,000
Net income (loss)	1,693,000	(352,000)	2,399,000	(785,000)
Provision (benefit) for income taxes	313,000	(103,000)	327,000	(226,000)
Interest expense (income), net (b)	13,000	(10,000)	11,000	(14,000)
Depreciation	8,000	4,000	22,000	9,000
EBITDA (c)	2,027,000	(461,000)	2,759,000	(1,016,000)
Capital expenditures		5,000		5,000
TOTAL ASSETS	76,777,000	71,680,000	76,777,000	71,680,000
Homebuilding
Segment Reporting Information [Line Items]
Revenues	202,000		202,000
Net income (loss)	(66,000)		(152,000)
Provision (benefit) for income taxes	(24,000)		(51,000)
EBITDA (c)	(90,000)		(203,000)
Capital expenditures	3,000		3,000
TOTAL ASSETS	1,494,000		1,494,000
Corporate
Segment Reporting Information [Line Items]
Revenues	65,000	340,000	415,000	682,000
Net income (loss)	(829,000)	(1,817,000)	(856,000)	(1,580,000)
Provision (benefit) for income taxes	30,000	(519,000)	189,000	(530,000)
Interest expense (income), net (b)	(1,000)	(131,000)	(5,000)	(251,000)
Depreciation	124,000	157,000	248,000	280,000
EBITDA (c)	(676,000)	(2,310,000)	(424,000)	(2,081,000)
Capital expenditures	0
TOTAL ASSETS	$ 17,449,000	$ 23,949,000	$ 17,449,000	$ 23,949,000