Note 10 - Income Taxes (Details) - Deferred Tax Assets and Liabilities (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred Tax Assets and Liabilities [Abstract]
Depreciation of property and equipment	$ 596	$ 646
Net operating loss ("NOL") (state and foreign)	513	829
Intangibles	224	162
Inventories	184us-gaap_DeferredTaxAssetsInventory	180us-gaap_DeferredTaxAssetsInventory
Accrued vacation pay and stock-based compensation	126	169
Tax credit carryforwards (foreign, research and AMT)	92	269
Allowance for doubtful accounts	56	56
Acquisition costs	34	37
Accrued warranty	6	11
Other	21us-gaap_DeferredTaxAssetsOther	26us-gaap_DeferredTaxAssetsOther
	1,852us-gaap_DeferredTaxAssetsGross	2,385us-gaap_DeferredTaxAssetsGross
Valuation allowance	(100)	(287)	(573)
Deferred tax assets	1,752us-gaap_DeferredTaxAssetsNet	2,098us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Net intangible assets	(232)	(260)
Unremitted earnings of foreign subsidiaries	(107)	(107)
Deferred tax liabilities	(339)us-gaap_DeferredIncomeTaxLiabilities	(367)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset	$ 1,413us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 1,731us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards that are expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from warranty reserves.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiaries and other recognized entities not within the country of domicile of the entity.

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