Organization and Significant Accounting Policies - Concentration of Credit Risk (Details) - Customer concentration	12 Months Ended
Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2024
Sales Revenue \| US Government Agencies
Concentration of Credit Risk
Concentration Risk, Percentage	85.00%	75.00%	76.00%
Sales Revenue \| US Army
Concentration of Credit Risk
Concentration Risk, Percentage	25.00%	20.00%	11.00%
Accounts receivable balances \| US Government Agencies
Concentration of Credit Risk
Concentration Risk, Percentage	76.00%	75.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References + Details