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Note 8 - Stock-based Incentive Plans (Details Textual) - USD ($) |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Apr. 01, 2025 | Mar. 15, 2021 | Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2026
Restricted Stock [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number (in shares) |  |  | 0 |  | 0
Share-Based Payment Arrangement, Expense |  |  | $ 34,000 |  |
Equity Incentive Plan 2016 [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) |  |  | 2,500,000 |  | 2,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) |  |  | 1,129,047 |  | 1,129,047
The Phantom Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year) |  | 10 years |  |  |
The Phantom Plan [Member] | Phantom Shares [Member] | Employees and Non-Employee Directors [Member] |  |  |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 0 | $ 0 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | 223,307 |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 2 years |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Payment Per Share (in dollars per share) | $ 12 |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares) |  |  |  |  | 111,652
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares) |  |  | 111,655 |  | 111,655
The Phantom Plan [Member] | Phantom Shares [Member] | Employees and Non-Employee Directors [Member] | Vesting Per Quarter [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage | 12.50% |  |  |  |
The Phantom Plan [Member] | Phantom Shares [Member] | Employees and Non-Employee Directors [Member] | Financial Results Based Award Vesting [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage | 6.25% |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Minimum Amount of Operating Profit Needed to Meet Service Condition | $ 150,000 |  |  |  |
The Phantom Plan [Member] | Phantom Shares [Member] | Employees and Non-Employee Directors [Member] | Stock Appreciation Based Award Vesting [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage | 6.25% |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Minimum Amount of Operating Profit Needed to Meet Service Condition | $ 150,000 |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Additional Financial Performance Condition Needed for Vesting Award | $ 300,000 |  |  |  |

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- Definition Represents the maximum payment value per share of equity instruments other than options under share based compensation arrangement. + References No definition available. + Details
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- Definition Represents the minimum amount of operating profit needed to meet the service condition in relation to a share-based payment award. + References No definition available. + Details
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(03) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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