SHARE-BASED COMPENSATION: (Details 2) (USD $)	9 Months Ended
	Dec. 31, 2014
Stock options outstanding and exercisable by exercise price range
Options outstanding (in shares)	5,684,363
Options outstanding - Weighted-average remaining contractual life	5 years 1 month 21 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 14.49
Options exercisable (in shares)	3,387,728
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 17.74
Range of exercise price per share from $0.63 to $8.90
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 0.63
Exercise price per share, high end of range (in dollars per share)	$ 8.90
Options outstanding (in shares)	1,411,953
Options outstanding - Weighted-average remaining contractual life	7 years 6 months 15 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 1.56
Options exercisable (in shares)	272,262
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 2.09
Range of exercise price per share from $11.08 to $14.42
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 11.08
Exercise price per share, high end of range (in dollars per share)	$ 14.42
Options outstanding (in shares)	1,715,499
Options outstanding - Weighted-average remaining contractual life	5 years 6 months 7 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 13.22
Options exercisable (in shares)	1,192,268
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 13.10
Range of exercise price per share from $15.10 to $19.76
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)	$ 19.76
Options outstanding (in shares)	651,390
Options outstanding - Weighted-average remaining contractual life	2 years 3 months 22 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 16.38
Options exercisable (in shares)	617,260
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 16.23
Range of exercise price per share from $20.44 to $25.00
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 20.44
Exercise price per share, high end of range (in dollars per share)	$ 25.00
Options outstanding (in shares)	1,571,693
Options outstanding - Weighted-average remaining contractual life	4 years 7 months 10 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 22.33
Options exercisable (in shares)	986,775
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 22.95
Range of exercise price per share from $26.33 to $35.16
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 26.33
Exercise price per share, high end of range (in dollars per share)	$ 35.16
Options outstanding (in shares)	203,007
Options outstanding - Weighted-average remaining contractual life	1 year 3 months 26 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 30.86
Options exercisable (in shares)	188,342
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 30.71
Range of exercise price per share from $41.38 to $62.06
Stock options outstanding and exercisable by exercise price range
Exercise price per share, low end of range (in dollars per share)	$ 41.38
Exercise price per share, high end of range (in dollars per share)	$ 62.06
Options outstanding (in shares)	130,821
Options outstanding - Weighted-average remaining contractual life	7 months 21 days
Options outstanding - Weighted-average exercise price per share (in dollars per share)	$ 41.83
Options exercisable (in shares)	130,821
Options exercisable - Weighted-average exercise price per share (in dollars per share)	$ 41.83