Note 9 Employee Equity Incentive Plans (Tables)

12 Months Ended

Mar. 31, 2013

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Year Ended March 31,
Income Statement Classifications	2013		2012		2011
Cost of goods sold	$	398	$	376	$	351
Research, development and engineering		1,030		917		650
Selling, general and administrative		2,023		2,486		2,397
Stock-based compensation effect on income before taxes		3,451		3,779		3,398
Benefit from income taxes		1,287		1,375		1,236
Net stock-based compensation effects on net income	$	2,164	$	2,404	$	2,162

Schedule of Employee Service Share-based Compensation Fair Value Assumptions and Methodology [Table Text Block]

		Stock Options						Purchase Plan
		Year Ended March 31,						Year Ended March 31,
		2013		2012		2011		2013		2012		2011
Weighted average estimated per share
	fair value of grant	$	5.26	$	6.42	$	4.79	$	3.22	$	3.14	$	2.85
Risk-free interest rate			1.1%		1.3%		2.0%		0.2%		0.2%		0.3%
Expected term in years			6.34		5.85		5.83		0.50		0.50		0.50
Volatility			55.3%		55.7%		56.1%		46.4%		51.6%		49.3%
Dividend yield			0%		0%		0%		0%		0%		0%

Schedule of Share-based Compensation, Stock Options Activity [Table Text Block]

	Stock compensation activity under our equity incentive plans for fiscal 2013, 2012 and 2011 is summarized below:
		Shares Available for Grant	Options Outstanding		Weighted Average Exercise Price per Share (4)
			Number of Shares (1)	Intrinsic Value(2)(3)
				(000)
Stock Options
Balances, March 31, 2010		1,819,552	5,188,273	$ 4,570	$ 9.32
	Options granted	(700,000)	700,000		$ 9.05
	Options exercised	-	(439,902)	$ 1,926	$ 7.33
	Options cancelled	-	(30,750)		$ 7.57
	Options expired	135,000	(217,853)		$ 19.55
Balances, March 31, 2011		1,254,552	5,199,768	$ 23,505	$ 9.03
	New shares authorized (5)	600,000	-
	Options granted	(966,000)	966,000		$ 12.37
	Options exercised	-	(478,264)	$ 2,862	$ 7.35
	Options cancelled	11,250	(164,500)		$ 8.30
	Options expired	-	(51,000)		$ 12.61
Balances, March 31, 2012		899,802	5,472,004	$ 19,532	$ 9.75
	Options granted	(455,000)	455,000		$ 9.93
	Plan authorization expired	(589)	-
	Options exercised	-	(153,131)	$ 443	$ 7.03
	Options cancelled	7,500	(67,425)		$ 8.34
	Options expired	-	(378,975)		$ 7.31
Balances, March 31, 2013		451,713	5,327,473	$ 4,273	$ 10.04
Restricted Stock Units (6)
Balances, March 31, 2010		(151,766)	32,200		$ 9.58
	Vested	-	(32,200)	$ 292	$ 9.58
Balances, March 31, 2011		(151,766)	-
Balances, March 31, 2013		299,947	5,327,473

(1) The number of stock options exercised and restricted stock units vested includes shares that were withheld on behalf of employees to satisfy the statutory tax withholding requirements.

(2) For restricted stock units, represents value of our stock on the date the restricted stock unit vests.

(3) Except for options exercised, these amounts represent the difference between the exercise price and $9.59 per share, the closing price of our stock on March 31, calyr as reported on the NASDAQ Global Select Market, for all in-the-money, outstanding and exercisable options.

(4) For restricted stock units, represents the weighted average fair value per share on the date of grant.

(5) On September 16, 2011, our stockholders approved the 2011 Plan, under which 600,000 shares of our common stock are reserved for the grant of stock options.

(6) No restricted stock units activities occurred in fiscal 2013 and 2012.

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Options Outstanding				Options Exercisable
Exercise Price per Share	Number of Shares Outstanding	Weighted Average Contractual Life	Weighted Average Exercise Price per Share	Number of Shares Exercisable	Weighted Average Exercise Price per Share
$5.01 - $7.75	1,205,735	5.2	$ 6.63	1,205,735	$ 6.63
$7.76 - $10.00	1,582,000	5.8	$ 9.21	1,044,500	$ 9.06
$10.01 - $12.50	1,611,950	6.1	$ 11.32	1,121,450	$ 11.11
$12.51 - $99.99	927,788	4.8	$ 13.65	693,788	$ 13.97
$5.01 - $99.99	5,327,473	5.6	$ 10.04	4,065,473	$ 9.74