Note 14 - Lease Financing Obligation (Details) - Interest Expense - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Design Tools [Member]
Note 14 - Lease Financing Obligation (Details) - Interest Expense [Line Items]
Interest expense	$ 45	$ 39	$ 93	$ 78

The financing charge for leasing arrangements meeting the criteria for capitalization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45031-112735

Name:	us-gaap_CapitalLeasesIncomeStatementInterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration