Note 5 - Income Taxes - Components of Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Current taxes
Federal	$ 7,352	$ 9,718	$ 15,012
State	841	1,538	1,586
Total current taxes	8,193	11,256	16,598
Deferred taxes
Federal	(135)	108	(83)
State	(16)	17	(9)
Total deferred taxes	(151)	125	(92)
Total provision for income taxes	$ 8,042	$ 11,381	$ 16,506

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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