Note 11 - Stock-based Compensation - Options Exercised (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 01, 2017	Dec. 27, 2015	Jan. 01, 2017	Dec. 27, 2015
Intrinsic value of options exercised	$ 1,367	$ 39	$ 4,085	$ 637

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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