Note 3 - Acquisition (Details) - Estimated Fair Value of Assets Acquired and Liabilities Assumed (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Intangible assets:
Goodwill	$ 6,571us-gaap_Goodwill	$ 6,571us-gaap_Goodwill
IPR&D [Member] \| Sensima [Member]
Intangible assets:
Intangible Assets	2,045
Sensima [Member] \| Know-How [Member]
Intangible assets:
Intangible Assets	1,018
Sensima [Member] \| Developed Technology Rights [Member]
Intangible assets:
Intangible Assets	4,421
Sensima [Member]
Note 3 - Acquisition (Details) - Estimated Fair Value of Assets Acquired and Liabilities Assumed [Line Items]
Cash	145
Other tangible assets acquired, net of liabilities assumed	42
Intangible assets:
Total identifiable net assets acquired	7,671
Goodwill	6,571
Total net assets acquired	$ 14,242

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Amount represents the aggregate value of other tangible assets acquired, net of liabilities assumed.

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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 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.

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

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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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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