Note 11 - Income Taxes - Reconciliation of Income Tax Rate (Details)	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Federal statutory rate	21.00%	21.00%
State and local taxes, net of federal benefit	2.90%	3.00%
Foreign operations	0.60%	0.00%
Federal tax credits	(1.00%)	(1.00%)
Uncertain tax position activity	0.00%	(0.30%)
Stock-based compensation	(1.20%)	(0.30%)
Tax rate changes	(0.20%)	(1.40%)
Other	0.60%	0.20%
Effective tax rate	22.70%	21.20%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage 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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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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