INCOME TAXES (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
INCOME TAXES
Provision for income taxes at statutory rate	$ 9,253	$ 11,360	$ 22,706
State tax provision (benefit) net of federal effect	143	265	(2)
Stock based compensation	(60)	107	616
Research tax credits	(589)	(289)	(432)
Qualifying manufacturing credits	(154)	(315)	(1,346)
Change in valuation allowance	154	(72)	314
Other	245	(20)	202
Provision for income taxes	$ 8,992	$ 11,036	$ 22,058

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the deduction for qualified production activities received under enacted tax laws.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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