STOCK-BASED COMPENSATION Stock Option Activity (Details) - Stock Options [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding at March 31, 2015	1,558
Options granted	141
Options exercised	(100)
Options forfeited or expired	(26)
Options outstanding at June 30, 2015	1,573
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted average exercise price of options outstanding, March 31, 2015	$ 36.59
Weighted average exercise price of options granted	53.91
Weighted average exercise price of options exercised	30.55
Weighted average exercise price of options forfeited or expired	46.67
Weighted average exercise price of options outstanding, June 30, 2015	$ 38.37
Weighted average remaining contractual life of options outstanding at June 30, 2015	4 years 37 days
Aggregate intrinsic value of options outstanding at June 30, 2015	$ 29,532
Vested and expected to vest at June 30, 2015	1,533
Weighted average exercise price of options vested and expected to vest at June 30, 2015	$ 38.06
Weighted average remaining contractual life of options vested and expected to vest at June 30, 2015	4 years
Aggregate intrinsic value of options vested and expected to vest at June 30, 2015	$ 29,248
Exercisable at June 30, 2015	1,083
Weighted average exercise price of options exercisable at June 30, 2015	$ 33.86
Weighted average remaining contractual life of options exercisable at June 30, 2015	3 years 73 days
Aggregate intrinsic value of options exercisable at June 30, 2015	$ 25,215
Total intrinsic value of options exercised	2,500	$ 2,000
Total cash received as a result of stock option exercises, net of taxes	3,100
Total unrecognized compensation cost related to unvested stock options	$ 4,400
Weighted average period of recognition for unrecognized compensation cost related to unvested stock options	2 years 37 days