FAIR VALUE MEASUREMENTS (Details) - Recurring basis - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Total fair value
Financial Assets
Total cash equivalents and short-term investments	$ 66,449	$ 76,317
Level 1
Financial Assets
Total cash equivalents and short-term investments	58,755	57,187
Level 1 | Treasury bills
Financial Assets
Total cash equivalents and short-term investments		5,403
Level 1 | Money market funds
Financial Assets
Total cash equivalents and short-term investments	58,755	51,784
Level 2
Financial Assets
Total cash equivalents and short-term investments	7,694	19,130
Level 2 | Corporate debentures/bonds
Financial Assets
Total cash equivalents and short-term investments	5,890	13,813
Level 2 | Government agency bonds
Financial Assets
Total cash equivalents and short-term investments	$ 1,804	$ 5,317