EQUITY COMPENSATION PLANS AND SHARE-BASED COMPENSATION (Details) (USD $)	12 Months Ended					12 Months Ended				12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2013 2005 Equity Incentive Plan [Member]	Mar. 31, 2013 1992 Outside Directors Stock Option Plan [Member]	Mar. 31, 2013 Stock Options [Member]	Mar. 31, 2012 Stock Options [Member]	Mar. 31, 2011 Stock Options [Member]	Mar. 31, 2010 Stock Options [Member]	Mar. 31, 2013 Stock Options [Member] Employees [Member]	Mar. 31, 2013 Stock Options [Member] Non-Employee Directors [Member]	Mar. 31, 2013 Stock Options [Member] Non-Employee Directors [Member] 1992 Outside Directors Stock Option Plan [Member]	Mar. 31, 2013 Cost of Revenues [Member]	Mar. 31, 2012 Cost of Revenues [Member]	Mar. 31, 2011 Cost of Revenues [Member]	Mar. 31, 2013 Research and Development [Member]	Mar. 31, 2012 Research and Development [Member]	Mar. 31, 2011 Research and Development [Member]	Mar. 31, 2013 Sales and Marketing [Member]	Mar. 31, 2012 Sales and Marketing [Member]	Mar. 31, 2011 Sales and Marketing [Member]	Mar. 31, 2013 General and Administrative [Member]	Mar. 31, 2012 General and Administrative [Member]	Mar. 31, 2011 General and Administrative [Member]
Equity Compensation Plan and Allocation of Share-based Compensation [Line Items]
Increase in aggregate number of shares reserved for issuance (in shares)				900,000
Amendment to the 2005 equity incentive plan (in shares)				500,000
Maximum shares authorized for issuance (in shares)				6,786,000	250,000
Shares available for future issuance (in shares)				1,109,000	0
Shares approved by the Board of Directors that have not been granted in accordance with ASC 718-10-55-95 (in shares)				63,000
Term of grant						10 years						10 years
Award vesting period										4 years	1 year	1 year
Stock options outstanding (in shares)						72,000	282,000	406,000	720,000			0
Share-based compensation expense before income taxes	$ 7,086,000	$ 5,683,000	$ 4,844,000										$ 921,000	$ 918,000	$ 656,000	$ 1,150,000	$ 866,000	$ 880,000	$ 2,506,000	$ 1,877,000	$ 1,499,000	$ 2,509,000	$ 2,022,000	$ 1,809,000
Income tax benefit	(2,557,000)	(2,001,000)	(1,815,000)
Total share-based compensation expense after income taxes	4,529,000	3,682,000	3,029,000
Net impact of share-based compensation on [Abstract]
Basic net income per share (in dollars per share)	$ 0.21	$ 0.17	$ 0.14
Diluted net income per share (in dollars per share)	$ 0.20	$ 0.16	$ 0.13
Capitalized share-based compensation costs	151,000	139,000	107,000
Excess tax benefits classified as financing cash inflow	$ 2,683,000	$ 862,000	$ 2,260,000