UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
NET EARNINGS	$ 18,003	$ 17,221	$ 33,276	$ 30,644
OTHER COMPREHENSIVE INCOME, NET OF TAX:
Foreign currency translation adjustments	(143)	391	(800)	703
Other comprehensive income (loss)	(143)	391	(800)	703
TOTAL COMPREHENSIVE INCOME	$ 17,860	$ 17,612	$ 32,476	$ 31,347