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Share-Based Compensation (Details Narrative) - USD ($)	3 Months Ended
Share-Based Compensation (Details Narrative) - USD ($)	Jul. 31, 2023	Jul. 31, 2022	Apr. 30, 2023	Jan. 31, 2023	Feb. 09, 2022	Feb. 08, 2022	Jan. 18, 2018	Dec. 31, 2015
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock	$ 600,000
Share-based compensation of weighted-average period	1 year 10 months 24 days
Shares outstanding	1,448,984		1,529,185
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options unvested	965,000
Weighted average remaining contractual term	9 years 1 month 6 days
Share-based payment arrangement, expense	$ 79,000	$ 96,000
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense	43,000	53,000
Shares outstanding			66,667
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 280,000	$ 184,000
Share-based compensation of weighted-average period	1 year 3 months 18 days
Number of restricted shares, granted	52,500	51,500
Unrecognized compensation cost	$ 844,000
2015 Omnibus Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement shares authorized				4,382,036				1,332,036
Share-based compensation arrangement shares aggregate increase				$ 3,050,000
Capital shares reserved for future issuance	365,000
2018 Inducement Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement shares authorized					275,000	250,000
Capital shares reserved for future issuance							25,000
Available for grant	111,000