Note 8 - Investment Securities - Investments by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Due in one year or less, Amortized Cost	$ 282,514
Due in one year or less, Fair Value	280,897
Due after one year through five years, Amortized Cost	176,541
Due after one year through five years, Fair Value	159,389
Due after five years through ten years, Amortized Cost	147,198
Due after five years through ten years, Fair Value	138,428
Due after ten years, Amortized Cost	971,058
Due after ten years, Fair Value	835,697
Total, Amortized Cost	1,577,311	$ 1,126,867
Total, Fair Value	$ 1,414,411	$ 1,127,309

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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