Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Securities available-for-sale, amortized cost	$ 898,463	$ 1,019,230
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	90,729,966	90,643,206
Common stock, shares outstanding (in shares)	79,595,025	79,508,265
Treasury stock shares (in shares)	11,134,941	11,134,941

Amortized cost 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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