COMPUTATION OF EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share [Abstract]
Net income	$ 20,387	$ 21,228
Earnings Per Share, Basic and Diluted [Abstract]
Weighted average common shares-basic	32,243	38,002
Dilutive effect of employee equity incentive plans	575	941
Weighted average common shares-diluted	32,818	38,943
Basic earnings per common share (in dollars per share)	$ 0.63	$ 0.56
Diluted earnings per common share (in dollars per share)	$ 0.62	$ 0.55
Potentially dilutive securities excluded from diluted earnings per common share because their effect is anti-dilutive	1,023	235