Note 2 - Acquisition of Businesses - Final Purchase Price Allocations (Details)	Jan. 02, 2016 USD ($)
Sigmar [Member] \| Patents [Member]
Patents	$ 2,845,000
Sigmar [Member]
Cash	230,000
Current assets, net	4,011,000
Property, plant and equipment	1,097,000
Goodwill	2,060,000
Current liabilities	(1,704,000)
Other non-current liabilities	(2,906,000)
	5,633,000
Sym Com Inc [Member] \| Patents [Member]
Patents	1,500,000
Sym Com Inc [Member] \| Trademarks [Member]
Patents	17,020,000
Sym Com Inc [Member]
Cash	325,000
Current assets, net	9,154,000
Property, plant and equipment	11,193,000
Goodwill	15,018,000
Current liabilities	(1,137,000)
	53,093,000
Other non-current assets	20,000
Goodwill	$ 189,767,000

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Name Accounting Standards Codification
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