Note 3 - Investment Securities - Summary of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
JPMorgan Managed Income Fund, fair value		$ 62,207
JPMorgan Managed Income Fund, cost		$ 62,178

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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