Amount of reduction (increase) to income tax expense due to the blended rate.

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 excess tax benefit for share-based compensation cost.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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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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Note 5 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
Note 5 - Income Taxes (Details Textual) - USD ($)	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		31.50%
Income Tax Expense Reduction (Increase) Due to Blended Rate		$ 1,900,000
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability		(430,000)
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount		(1,086,000)
Tax Adjustments, Settlements, and Unusual Provisions		150,000
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total		$ 0