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Share-Based Compensation Plans (Details Narrative) - USD ($)	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022	Feb. 09, 2022	Feb. 08, 2022	Jan. 18, 2018	Dec. 31, 2015
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, granted	601,089
Total unrecognized compensation	$ 700,000
Share-based compensation of weighted-average period	2 years 3 months 18 days
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, granted	601,089	793,850
Intrinsic value	$ 0
Options unvested	513,000
Weighted average remaining contractual term	7 years 8 months 12 days
Share-based payment arrangement, expense	$ 300,000	$ 300,000
Employee Stock Option One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Intrinsic value	0
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Intrinsic value	$ 0
Options unvested	66,667
Weighted average remaining contractual term	8 years 1 month 6 days
Share-based payment arrangement, expense	$ 100,000	100,000
Total unrecognized compensation	$ 4,000
Share-based compensation of weighted-average period	1 month 6 days
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 1,100,000	$ 200,000
Share-based compensation of weighted-average period	1 year 4 months 24 days
Number of restricted shares, granted	1,608,681	827,764
Unrecognized compensation cost	$ 1,100,000
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	221,446
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	161,487