STOCK-BASED COMPENSATION Stock Option Activity (Details) (Stock Options, USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2013
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding at March 31, 2012	3,304,000
Options granted	428,000
Options exercised	(1,110,000)
Options forfeited or expired	(207,000)
Options outstanding at March 31, 2013	2,415,000
Weighted average exercise price of options outstanding at March 31, 2012	$ 26.47
Weighted average exercise price of options granted	$ 33.23
Weighted average exercise price of options exercised	$ 24.37
Weighted average exercise price of options forfeited or expired	$ 34.45
Weighted average exercise price of options outstanding at March 31, 2013	$ 27.96
Weighted average remaining contractual life of options outstanding at March 31, 2013	3 years 219 days
Aggregate intrinsic value of options outstanding at March 31, 2013	$ 39,206
Vested and expected to vest at March 31, 2013	2,388,000
Weighted average exercise price of options vested and expected to vest at March 31, 2013	$ 27.89
Weighted average remaining contractual life of options vested and expected to vest at March 31, 2013	3 years 219 days
Aggregate intrinsic value of options vested and expected to vest at March 31, 2013	38,919
Exercisable at March 31, 2013	1,713,000
Weighted average exercise price of options exercisable at March 31, 2013	$ 25.56
Weighted average remaining contractual life of options exercisable at March 31, 2013	2 years 256 days
Aggregate intrinsic value of options exercisable at March 31, 2013	$ 31,918