Note 3 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Securities available for sale, amortized cost	$ 445,220	$ 274,709
Securities available for sale, gross unrealized gains	5,912	8,830
Securities available for sale, gross unrealized losses	3,797	37
Securities available for sale, at fair value	447,335	283,502
Securities held to maturity, amortized cost	2,000	0
Securities held to maturity, gross unrealized gains	4
Securities held to maturity, gross unrealized losses	0
Securities held to maturity, fair value	2,004
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	102,767	59,997
Securities available for sale, gross unrealized gains	604	1,362
Securities available for sale, gross unrealized losses	635	0
Securities available for sale, at fair value	102,736	61,359
Agency Collateralized Mortgage Obligations [Member]
Securities available for sale, amortized cost	7,863	20,842
Securities available for sale, gross unrealized gains	98	218
Securities available for sale, gross unrealized losses	0	30
Securities available for sale, at fair value	7,961	21,030
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	130,641	80,359
Securities available for sale, gross unrealized gains	489	1,175
Securities available for sale, gross unrealized losses	2,034	3
Securities available for sale, at fair value	129,096	81,531
US Treasury and Government [Member]
Securities available for sale, amortized cost	50,339
Securities available for sale, gross unrealized gains	0
Securities available for sale, gross unrealized losses	545
Securities available for sale, at fair value	49,794
Municipal Notes [Member]
Securities available for sale, amortized cost	153,610	113,511
Securities available for sale, gross unrealized gains	4,721	6,075
Securities available for sale, gross unrealized losses	583	4
Securities available for sale, at fair value	157,748	$ 119,582
Corporate Note Securities [Member]
Securities held to maturity, amortized cost	2,000
Securities held to maturity, gross unrealized gains	4
Securities held to maturity, gross unrealized losses	0
Securities held to maturity, fair value	$ 2,004

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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