Note 12 - Industry Segmentation and Sales by Major Customer - Schedule of Revenue by Major Customers by Reporting Segments (Details) (Parentheticals) |
Apr. 30, 2019 |
Apr. 30, 2018 |
---|---|---|
Aerospace Products [Member] | Customer Concentration Risk [Member] | Revenue Benchmark [Member] | ||
Number of customers | 1 | 1 |