Note 2 - Supplemental Balance-sheet Information - Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill	$ 1,907	$ 1,907
Customer Relationships [Member]
Gross carrying amount	906	906
Accumulated amortization	(440)	(418)
Computer Software, Intangible Asset [Member]
Gross carrying amount	234	234
Accumulated amortization	(228)	(216)
Trade Names [Member]
Gross carrying amount	60	60
Accumulated amortization	$ (7)	$ (5)

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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