Investments - Schedule of Investments (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jul. 31, 2019	Apr. 30, 2019
Cost Basis	$ 23,597,000	$ 23,425,000
Gross Unrealized Gains	4,372,000	4,223,000
Gross Unrealized Losses	(312,000)	(357,000)
Fair Value	27,657,000	27,291,000
Municipal Bonds [Member]
Cost Basis	5,475,000	5,459,000
Gross Unrealized Gains	117,000	79,000
Gross Unrealized Losses	(43,000)	(55,000)
Fair Value	5,549,000	5,483,000
Corporate Bonds [Member]
Cost Basis	26,000	26,000
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	26,000	26,000
REITs [Member]
Cost Basis	89,000	89,000
Gross Unrealized Gains	3,000	1,000
Gross Unrealized Losses	(9,000)	(6,000)
Fair Value	83,000	84,000
Equity Securities [Member]
Cost Basis	16,729,000	16,618,000
Gross Unrealized Gains	4,252,000	4,143,000
Gross Unrealized Losses	(260,000)	(296,000)
Fair Value	20,721,000	20,465,000
Money Markets and CDs [Member]
Cost Basis	1,278,000	1,233,000
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	$ 1,278,000	$ 1,233,000