FAIR VALUE MEASUREMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 30, 2014 Maximum	Sep. 30, 2014 Short-term investments.	Mar. 31, 2014 Short-term investments.	Sep. 30, 2014 Short-term investments. Treasury bills	Sep. 30, 2014 Short-term investments. Corporate debentures/bonds	Mar. 31, 2014 Short-term investments. Corporate debentures/bonds	Sep. 30, 2014 Short-term investments. Government agency bonds	Mar. 31, 2014 Short-term investments. Government agency bonds	Mar. 31, 2014 Short-term investments. Commercial paper	Mar. 31, 2014 Short-term investments. Treasury bills	Sep. 30, 2014 Cash equivalents	Mar. 31, 2014 Cash equivalents	Sep. 30, 2014 Cash equivalents Money market funds	Mar. 31, 2014 Cash equivalents Money market funds	Mar. 31, 2014 Cash equivalents Corporate debentures/bonds
Available-for-sale securities
Contractual maturity period	16 months
Amortized Cost		$ 76,369	$ 88,629	$ 17,704	$ 32,032	$ 38,076	$ 26,633	$ 26,652	$ 6,193	$ 17,708	$ 34,762	$ 36,973	$ 34,762	$ 33,623	$ 3,350
Gross Unrealized Gains		27	33	17	1	9	9	10		14
Gross Unrealized Losses		(37)	(13)		(37)	(11)		(2)
Fair Value		$ 76,359	$ 88,649	$ 17,721	$ 31,996	$ 38,074	$ 26,642	$ 26,660	$ 6,193	$ 17,722	$ 34,762	$ 36,973	$ 34,762	$ 33,623	$ 3,350