STOCKHOLDERS' EQUITY: (Details 3) (USD $)	12 Months Ended
	Mar. 31, 2012 Y
Stock options outstanding and exercisable by exercise price range
Options outstanding (in shares)	8,322,077
Options outstanding - Weighted-average remaining contractual life (in years)	4.13
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 20.91
Options exercisable (in shares)	7,390,173
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 21.84
Range of exercise price per share from $3.69 to $9.62
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 3.69
Exercise price per share, high end of range (in dollars per share)	$ 9.62
Options outstanding (in shares)	128,457
Options outstanding - Weighted-average remaining contractual life (in years)	5.79
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 8.61
Options exercisable (in shares)	74,457
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 8.41
Range of exercise price per share from $10.22 to $15.00
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 10.22
Exercise price per share, high end of range (in dollars per share)	$ 15.00
Options outstanding (in shares)	2,020,341
Options outstanding - Weighted-average remaining contractual life (in years)	6.39
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 12.90
Options exercisable (in shares)	1,177,151
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 12.37
Range of exercise price per share from $15.10 to $19.82
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 15.10
Exercise price per share, high end of range (in dollars per share)	$ 19.82
Options outstanding (in shares)	2,021,967
Options outstanding - Weighted-average remaining contractual life (in years)	3.69
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 16.61
Options exercisable (in shares)	1,987,253
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 16.59
Range of exercise price per share from $20.12 to $25.00
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 20.12
Exercise price per share, high end of range (in dollars per share)	$ 25.00
Options outstanding (in shares)	2,122,378
Options outstanding - Weighted-average remaining contractual life (in years)	3.97
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 22.92
Options exercisable (in shares)	2,122,378
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 22.92
Range of exercise price per share from $25.98 to $29.30
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 25.98
Exercise price per share, high end of range (in dollars per share)	$ 29.30
Options outstanding (in shares)	1,106,336
Options outstanding - Weighted-average remaining contractual life (in years)	2.44
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 26.70
Options exercisable (in shares)	1,106,336
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 26.70
Range of exercise price per share from $30.93 to $39.12
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 30.93
Exercise price per share, high end of range (in dollars per share)	$ 39.12
Options outstanding (in shares)	679,996
Options outstanding - Weighted-average remaining contractual life (in years)	2.19
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 35.79
Options exercisable (in shares)	679,996
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 35.79
Range of exercise price per share from $40.50 to $62.06
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 40.50
Exercise price per share, high end of range (in dollars per share)	$ 62.06
Options outstanding (in shares)	242,602
Options outstanding - Weighted-average remaining contractual life (in years)	2.55
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 44.08
Options exercisable (in shares)	242,602
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 44.08