Note 4 - Detail of Certain Asset Accounts (Details) (USD $)	3 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended
Jun. 27, 2014	Jun. 28, 2013	Mar. 31, 2014	Jun. 27, 2014 Patents [Member]	Mar. 31, 2014 Patents [Member]	Jun. 27, 2014 Patents [Member] Maximum [Member]	Jun. 27, 2014 Other Intangible Assets [Member]	Mar. 31, 2014 Other Intangible Assets [Member]
Note 4 - Detail of Certain Asset Accounts (Details) [Line Items]
Amortization of Intangible Assets	$ 205,000	$ 250,000
Finite-Lived Intangible Asset, Useful Life				10 years	10 years	20 years
Finite-Lived Intangible Assets, Gross	$ 15,496,000		$ 15,461,000	$ 1,335,000	$ 1,108,000		$ 603,000	$ 795,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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