Note 3 - Investment Securities - Amortized Cost and Fair Value of Available for Sale Securities and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Available for sale, Amortized Cost	$ 328,881	$ 347,070
Available for sale, gross unrealized gains	1,020	620
Available for sale, gross unrealized losses	(24,235)	(28,729)
Available for sale	305,666	318,961
Held to maturity (fair value of $5,087 and $5,097 at September 30, 2024 and December 31, 2023)	5,195	5,209
Held to maturity, gross unrealized gains	2	3
Held to maturity, gross unrealized losses	(110)	(115)
Securities held to maturity, fair value	5,087	5,097
US Government Agencies Debt Securities [Member]
Available for sale, Amortized Cost	6,745	8,705
Available for sale, gross unrealized gains	0	0
Available for sale, gross unrealized losses	(286)	(544)
Available for sale	6,459	8,161
Small Business Administration Agency Securities [Member]
Available for sale, Amortized Cost	26,877	13,289
Available for sale, gross unrealized gains	202	144
Available for sale, gross unrealized losses	(149)	(216)
Available for sale	26,930	13,217
Residential Mortgage-Backed Securities [Member]
Available for sale, Amortized Cost	41,278	40,507
Available for sale, gross unrealized gains	26	0
Available for sale, gross unrealized losses	(4,860)	(5,855)
Available for sale	36,444	34,652
Residential Collateralized Mortgage Obligations [Member]
Available for sale, Amortized Cost	103,084	94,071
Available for sale, gross unrealized gains	560	454
Available for sale, gross unrealized losses	(10,458)	(12,198)
Available for sale	93,186	82,327
Commercial Collateralized Mortgage Obligations [Member]
Available for sale, Amortized Cost	79,024	69,941
Available for sale, gross unrealized gains	183	22
Available for sale, gross unrealized losses	(2,283)	(2,664)
Available for sale	76,924	67,299
Commercial Paper [Member]
Available for sale, Amortized Cost	24,512	73,121
Available for sale, gross unrealized gains	1	0
Available for sale, gross unrealized losses	0	(16)
Available for sale	24,513	73,105
Corporate Debt Securities [Member]
Available for sale, Amortized Cost	34,751	34,800
Available for sale, gross unrealized gains	48	0
Available for sale, gross unrealized losses	(3,067)	(4,109)
Available for sale	31,732	30,691
Municipal Bonds [Member]
Available for sale, Amortized Cost	12,610	12,636
Available for sale, gross unrealized gains	0	0
Available for sale, gross unrealized losses	(3,132)	(3,127)
Available for sale	9,478	9,509
Held to maturity (fair value of $5,087 and $5,097 at September 30, 2024 and December 31, 2023)	4,695	4,708
Held to maturity, gross unrealized gains	0	0
Held to maturity, gross unrealized losses	(110)	(115)
Securities held to maturity, fair value	4,585	4,593
Taxable Municipal Bonds [Member]
Held to maturity (fair value of $5,087 and $5,097 at September 30, 2024 and December 31, 2023)	500	501
Held to maturity, gross unrealized gains	2	3
Held to maturity, gross unrealized losses	0	0
Securities held to maturity, fair value	$ 502	$ 504

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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