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Share-Based Compensation Plans (Details Narrative) - USD ($)		12 Months Ended
	Feb. 09, 2022	Apr. 30, 2024	Apr. 30, 2023	Jan. 18, 2018	Dec. 31, 2015
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, granted
Total unrecognized compensation		$ 200,000
Share-based compensation of weighted-average period		1 year 4 months 24 days
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, granted		0	601,089
Options, outstanding, intrinsic value		$ 0
Options unvested		272,000
Weighted average remaining contractual term		8 years 6 months
Share-based payment arrangement, expense		$ 100,000	$ 300,000
Employee Stock Option One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options, outstanding, intrinsic value		0
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options unvested			66,667
Share-based payment arrangement, expense		43,000	$ 108,000
Total unrecognized compensation		0
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, expense		$ 1,000,000.0	$ 1,100,000
Share-based compensation of weighted-average period		1 year 6 months
Number of restricted shares, granted		4,439,257	1,608,681
Unrecognized compensation cost		$ 1,400,000
2015 Omnibus Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement shares authorized		7,282,036			1,332,036
Share-based compensation arrangement shares aggregate increase		$ 2,900,000
2018 Inducement Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement shares authorized	275,000
Capital shares reserved for future issuance				25,000
Share-based compensation arrangement additional shares authorized	250,000