Note 9 Employee Equity Incentive Plans (Option and RSU Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Mar. 31, 2011		Mar. 31, 2010
Options Outstanding Intrinsic Value [Abstract]
Aggregate Intrinsic Value, Outstanding	$ 4,273	[1]	$ 19,532	[1]	$ 23,505	[1]	$ 4,570	[1]
Aggregate Intrinsic Value, Exercised	443		2,862		1,926
Restricted Stock Units (RSU) Shares Available for Grant
Beginning Balance	(151,766)	[2]	(151,766)		(151,766)
RSU Granted in Period	0		0		0
Ending Balance	(151,766)	[2]	(151,766)	[2]	(151,766)
RSU Nonvested Roll Forward
Beginning Balance			0		32,200
RSU Vested in Period, Shares					(32,200)	[3]
Ending Balance					0
RSU Vested in Period, Intrinsic Value					$ 292	[4]
RSU Nonvested, Weighted Average Grant Date Fair Value							$ 9.58	[5]
RSU Vested in Period, Weighted Average Grant Date Fair Value					$ 9.58	[5]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]
Beginning Balance	899,802		1,254,552		1,819,552
New Shares Authorized			600,000	[6]
Options Granted	(455,000)		(966,000)		(700,000)
Plan Authorization Expired	(589)
Options Cancelled	7,500		11,250
Options Expired					135,000
Ending Balance	451,713		899,802		1,254,552
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Share-based Payment Award, Number of Shares Available for Grant	299,947
Share-based Payment Award, Outstanding Number	5,327,473
Market Price of Company Stock	$ 9.59
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning Balance	5,472,004		5,199,768		5,188,273
Options Granted	455,000		966,000		700,000
Options Exercised	(153,131)	[3]	(478,264)	[3]	(439,902)	[3]
Options Cancelled	(67,425)		(164,500)		(30,750)
Options Expired	(378,975)		(51,000)		(217,853)
Ending Balance	5,327,473		5,472,004		5,199,768
Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price Per Share (Options Outstanding)	$ 10.04		$ 9.75		$ 9.03		$ 9.32
Options Granted	$ 9.93		$ 12.37		$ 9.05
Options Exercised	$ 7.03		$ 7.35		$ 7.33
Options Cancelled	$ 8.34		$ 8.30		$ 7.57
Options Expired	$ 7.31		$ 12.61		$ 19.55

[1] Represents the difference between the exercise price and $9.59 per share, the closing price of our stock on March 31, 2013 as reported on the NASDAQ Global Select Market, for all in-the-money, outstanding and exercisable options.

[2] No restricted stock units activities occurred in fiscal 2013 and 2012.

[3] The number of stock option exercised and restricted stock units vested includes shares that were withheld on behalf of employees to satisfy the statutory tax withholding requirements.

[4] Represents value of our stock on the date the restricted stock unit vests.

[5] Represents the weighted average fair value per share on the date of grant.

[6] 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.