Note 3 - Equity 2 (Details Textual) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Location, Statement of Income, Balance [Axis]: us-gaap:ResearchandDevelopmentExpense | RF Innovations, Inc. [Member] | ||
| Share-Based Payment Arrangement, Expense | $ 0.1 | |
| Share-Based Payment Arrangement, Option [Member] | Location, Statement of Income, Balance [Axis]: us-gaap:GeneralandAdministrativeExpense | ||
| Share-Based Payment Arrangement, Expense | $ 3.6 | 1.3 |
| Share-Based Payment Arrangement, Option [Member] | Location, Statement of Income, Balance [Axis]: us-gaap:ResearchandDevelopmentExpense | ||
| Share-Based Payment Arrangement, Expense | $ 0.6 | $ 0.2 |