Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jul. 31, 2021	Apr. 30, 2021
Payables and Accruals [Abstract]
Project costs	$ 198	$ 368
Contract loss reserve	328	328
Employee incentive payments	323	283
Accrued salary and benefits	598	631
Legal and accounting fees	292	200
Other	82	71
Accrued expenses total	$ 1,821	$ 1,881

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable for the acquisition of merchandise, materials, supplies and services pertaining to construction projects such as a housing development or factory expansion not classified as trade payables. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of obligations incurred for employer-related costs classified as other, payable within one year or the normal operating cycle, if longer.

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