Note 8 - Income Taxes (Details Textual) $ in Thousands	3 Months Ended
Jun. 30, 2019 USD ($)
Unrecognized Tax Benefits, Ending Balance	$ 0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	0
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 0
Open Tax Year	2015 2016 2017 2018

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

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Amount of unrecognized tax benefits.

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Amount of interest expense accrued for an underpayment of income taxes.

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