Note 15 - Accumulated Other Comprehensive Income ("AOCI") - Summary of Changes in AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Balance	$ 46,441	$ 53,755
Net increase in other comprehensive income	2
Balance	39,568	46,441
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Including Noncontrolling Interest [Member]
Balance
Other comprehensive income before reclassifications	2
Amounts reclassified from accumulated other comprehensive income
Net increase in other comprehensive income	2
Balance	2
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Balance
Other comprehensive income before reclassifications	2
Amounts reclassified from accumulated other comprehensive income
Net increase in other comprehensive income	2
Balance	$ 2

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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