Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Available-for-sale securities, amortized costs	$ 573,362	$ 436,249
Available-for-sale securities, gross unrealized gain	9,221	10,933
Available-for-sale securities, gross unrealized loss	(2,919)	(302)
Debt Securities, Available-for-sale	579,664	446,880
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized costs	28,903	32,164
Available-for-sale securities, gross unrealized gain	822	838
Available-for-sale securities, gross unrealized loss	(34)	(8)
Debt Securities, Available-for-sale	29,691	32,994
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized costs	132,675	103,424
Available-for-sale securities, gross unrealized gain	4,366	4,971
Available-for-sale securities, gross unrealized loss	(574)	(29)
Debt Securities, Available-for-sale	136,467	108,366
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized costs	317,157	236,829
Available-for-sale securities, gross unrealized gain	2,697	3,895
Available-for-sale securities, gross unrealized loss	(2,012)	(246)
Debt Securities, Available-for-sale	317,842	240,478
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized costs	52,484	27,455
Available-for-sale securities, gross unrealized gain	532	637
Available-for-sale securities, gross unrealized loss	(298)	(18)
Debt Securities, Available-for-sale	52,718	28,074
Asset-backed Securities [Member]
Available-for-sale securities, amortized costs	42,143	36,377
Available-for-sale securities, gross unrealized gain	804	592
Available-for-sale securities, gross unrealized loss	(1)	(1)
Debt Securities, Available-for-sale	$ 42,946	$ 36,968

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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