Note 2 - Income Tax Expense - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details)	6 Months Ended
Jun. 30, 2019 USD ($)
Unrecognized tax benefits as of December 31, 2018	$ 711,000
Additions for tax positions of current year	37,000
Additions for tax positions of prior years	5,000
Reductions for settlements with taxing authorities
Reductions for lapses of the applicable statutes of limitations
Unrecognized tax benefits as of June 30, 2019	$ 753,000

Amount of unrecognized tax benefits.

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