SHARE-BASED COMPENSATION: (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2014
Option Activity - Number of Shares
Outstanding at the beginning of the period (in shares)	4,538,518
Granted (in shares)	381,509
Exercised (in shares)	(14,137)
Forfeited or cancelled (in shares)	(520,923)
Outstanding at the end of the period (in shares)	4,384,967
Exercisable at the end of the period (in shares)	3,152,528
Weighted-average exercise price per share
Outstanding at the beginning of the period (in dollars per share)	$ 20.30
Granted (in dollars per share)	$ 21.17
Exercised (in dollars per share)	$ 18.79
Forfeited or cancelled (in dollars per share)	$ 34.66
Outstanding at the end of the period (in dollars per share)	$ 18.67
Exercisable at the end of the period (in dollars per share)	$ 19.09
Weighted-average remaining contractual term
Outstanding at the end of the period	4 years 8 months 23 days
Exercisable at the end of the period	3 years 3 months
Aggregate intrinsic value
Exercised	$ 50
Outstanding at the end of the period	19,297
Exercisable at the end of the period	$ 14,034
Stock Option and Equity Compensation Plans [Member]
Share-based compensation
Aggregate number of shares reserved for issuance under equity compensation plans since the inception of such plans	26,400,000
Shares which remained available for future grants	3,300,000
Employee Stock Option [Member]
Share-based compensation
Granted (in shares)	381,509
Per-share weighted-average fair value of the stock options granted (in dollars per share)	$ 8.14
Pricing model used for share-based compensation arrangement	binomial lattice
Dividend yield (as a percent)	0.00%
Risk-free interest rate (as a percent)	0.025%
Expected option life	4 years 4 months 24 days
Expected volatility (as a percent)	0.43%
Suboptimal exercise multiple	1.4