Note 5 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-Based Payment Arrangement, Amount	$ 33,000	$ (135,000)	$ 322,000
Tax Adjustments, Settlements, and Unusual Provisions	$ (29,000)	(194,000)	$ (93,000)
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total		$ 0

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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-Name Accounting Standards Codification
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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