Note 2 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Securities available for sale, amortized cost	$ 507,947	$ 445,220
Securities available for sale, gross unrealized gains	15	5,912
Securities available for sale, gross unrealized losses	52,683	3,797
Securities available for sale, at fair value	455,279	447,335
Securities held to maturity, amortized cost	7,000	2,000
Securities held to maturity, gross unrealized gains	0	4
Securities held to maturity, gross unrealized losses	1,382	0
Securities held to maturity, fair value	5,618	2,004
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	98,891	102,767
Securities available for sale, gross unrealized gains	0	604
Securities available for sale, gross unrealized losses	12,182	635
Securities available for sale, at fair value	86,709	102,736
Agency Collateralized Mortgage Obligations [Member]
Securities available for sale, amortized cost	7,602	7,863
Securities available for sale, gross unrealized gains	0	98
Securities available for sale, gross unrealized losses	370	0
Securities available for sale, at fair value	7,232	7,961
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	150,716	130,641
Securities available for sale, gross unrealized gains	0	489
Securities available for sale, gross unrealized losses	13,369	2,034
Securities available for sale, at fair value	137,347	129,096
US Treasury and Government [Member]
Securities available for sale, amortized cost	83,528	50,339
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	4,107	545
Securities available for sale, at fair value	79,421	49,794
Municipal Notes [Member]
Securities available for sale, amortized cost	167,210	153,610
Securities available for sale, gross unrealized gains	15	4,721
Securities available for sale, gross unrealized losses	22,655	583
Securities available for sale, at fair value	144,570	157,748
Corporate Note Securities [Member]
Securities held to maturity, amortized cost	7,000	2,000
Securities held to maturity, gross unrealized gains	0	4
Securities held to maturity, gross unrealized losses	1,382	0
Securities held to maturity, fair value	$ 5,618	$ 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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