Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available-for-sale, amortized cost	$ 1,443,730	$ 1,267,731
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)	90,064,382	89,826,317
Common stock, shares outstanding (in shares)	79,729,419	80,501,948
Treasury stock shares (in shares)	10,334,963	9,324,369