Note 9 - Income Taxes - Schedule of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Balance	$ 1,937	$ 3,399	$ 6,776
Additions for tax positions of prior years	948		10
Additions for tax positions in current period	642		228
Reductions for tax positions of prior years		(89)	(30)
Reductions due to expiration of statutory periods	(317)	(895)	(3,585)
Reductions due to settlements with taxing authorities		(478)
Balance	$ 3,210	$ 1,937	$ 3,399

Amount of unrecognized tax benefits.

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