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Share-Based Compensation (Details Narrative) - USD ($)	3 Months Ended		6 Months Ended
Share-Based Compensation (Details Narrative) - USD ($)	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 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	$ 400,000		$ 400,000
Share-based compensation of weighted-average period			1 year 9 months 18 days
Shares outstanding	1,183,491		1,183,491		1,529,185
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options unvested	766,000		766,000
Weighted average remaining contractual term			8 years 9 months 18 days
Share-based payment arrangement, expense	$ 20,000	$ 72,000	$ 98,000	$ 168,000
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense	0	48,000	43,000	101,000
Shares outstanding					66,667
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense	252,000	$ 180,000	$ 532,000	$ 364,000
Share-based compensation of weighted-average period			1 year 2 months 12 days
Number of restricted shares, granted			58,000	52,500
Unrecognized compensation cost	$ 554,000		$ 554,000
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	684,000		684,000
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		111,000