Note 11 - Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Federal statutory tax provision	$ (1,546)	$ (1,986)
State tax provision	(85)	(133)
Stock compensation expense	234	768
Tax credits	(2,974)	(2,682)
Foreign tax, net	2,430	2,104
Other	(1)	186
Total income tax benefit	$ (1,942)	$ (1,743)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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