Note 1 - Nature of Operations, Organization and Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended	24 Months Ended
Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2022
Duration after Which Invoices Are Considered to Be Doubtful (Day)			90 days
Duration During Which Inventory If Inactive Taken as Obsolete (Year)			5 years
Inventory Valuation Reserves	$ 240	$ 691	$ 240
Period for Payment Due (Day)			30 days
Cash, Uninsured Amount	7,835	16,883	$ 7,835
Research and Development Expense, Total	2,352	3,493
Kansas Lottery Commission and the Kansas Racing and Gaming Commission [Member]
Accrued Liabilities, Total	1,968	1,868	1,968
Kansas Expanded Lottery Act Management Contract Privilege Fee [Member]
Finite-Lived Intangible Assets, Gross, Total	5,500	5,500	5,500
Gaming Equipment [Member]
Finite-Lived Intangible Assets, Gross, Total	6,151	5,927	$ 6,151
Finite-Lived Intangible Asset, Useful Life (Year)			3 years
JET Autopilot Intellectual Property [Member]
Finite-Lived Intangible Assets, Gross, Total	1,417	1,417	$ 1,417
Finite-Lived Intangible Asset, Useful Life (Year)			15 years
Other Miscellaneous Long-Term Assets [Member]
Finite-Lived Intangible Assets, Gross, Total	128		$ 128
Amortization of Intangible Assets	689	733
Supplemental Type Certificates [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			7 years
Amortization of Intangible Assets	$ 1,295	$ 1,012
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)			3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)			39 years

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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.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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