Note 10 - Employee Equity Incentive Plans - Fair Value and Assumptions (Details) - $ / shares			12 Months Ended
		Oct. 01, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Employee Stock Option [Member]
Weighted average estimated per share fair value of grant (in dollars per share)			$ 4.83	$ 5.54	$ 5.31
Risk-free interest rate			1.80%	1.80%	1.80%
Expected term in years			6 years 164 days	6 years 91 days	6 years 18 days
Volatility			44.90%	52.20%	54.90%
Dividend yield	[1]		1.20%	1.00%	1.00%
Employee Stock Purchase Plan 1999 [Member]
Weighted average estimated per share fair value of grant (in dollars per share)			$ 3.33	$ 2.90	$ 2.75
Risk-free interest rate			0.10%	0.10%	0.10%
Expected term in years			182 days	182 days	182 days
Volatility			39.80%	36.90%	37.00%
Dividend yield	[1]		1.10%	1.10%	0.00%
Dividend yield		0.00%

[1] Prior to October 1, 2013, the fair value of our equity awards was based on 0% dividend yield.