Note 7 - Changes in Shareholders' Equity - Schedule of Changes in Shareholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Balance	$ 115,731
Net income	12,582	$ 9,276
Balance	123,881
Additional Paid-in Capital [Member]
Balance	9,381
Share based compensation	719
Dividends declared
Net income
Balance	10,100
Retained Earnings [Member]
Balance	106,320
Share based compensation
Dividends declared	(5,151)
Net income	12,582
Balance	$ 113,751

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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