Note 4 - Fair Value (Details) - Amortized Cost and Estimated Fair Value of Cash Equivalents and Marketable Securities (USD $) In Thousands, unless otherwise specified	Dec. 29, 2013	Mar. 31, 2013
Amortized Cost and Estimated Fair Value of Cash Equivalents and Marketable Securities [Abstract]
Less than 1 year	$ 61,616	$ 61,011
Less than 1 year	61,615	61,029
Due in 1 to 5 years	107,172	134,289
Due in 1 to 5 years	107,048	134,600
Total	168,788	195,300
Total	$ 168,663	$ 195,629