Note 2 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Securities available for sale, amortized cost	$ 347,738	$ 274,709
Securities available for sale, gross unrealized gains	7,039	8,830
Securities available for sale, gross unrealized losses	1,295	37
Securities available for sale, fair value	353,482	283,502
Securities held to maturity, amortized cost	2,000	0
Securities held to maturity, gross unrealized gains	25
Securities held to maturity, gross unrealized losses	0
Securities held to maturity, fair value	2,025
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	86,206	59,997
Securities available for sale, gross unrealized gains	960	1,362
Securities available for sale, gross unrealized losses	191	0
Securities available for sale, fair value	86,975	61,359
Agency Collateralized Mortgage Obligations [Member]
Securities available for sale, amortized cost	11,407	20,842
Securities available for sale, gross unrealized gains	218	218
Securities available for sale, gross unrealized losses	11	30
Securities available for sale, fair value	11,614	21,030
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	109,489	80,359
Securities available for sale, gross unrealized gains	798	1,175
Securities available for sale, gross unrealized losses	736	3
Securities available for sale, fair value	109,551	81,531
Municipal Notes [Member]
Securities available for sale, amortized cost	140,636	113,511
Securities available for sale, gross unrealized gains	5,063	6,075
Securities available for sale, gross unrealized losses	357	4
Securities available for sale, fair value	145,342	$ 119,582
Corporate Note Securities [Member]
Securities held to maturity, amortized cost	2,000
Securities held to maturity, gross unrealized gains	25
Securities held to maturity, gross unrealized losses	0
Securities held to maturity, fair value	$ 2,025

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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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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