Note 4 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost	$ 192,998	$ 165,817
Gross unrealized gains	52	4,922
Gross unrealized losses	(28,083)	(540)
Investment securities available for sale, at fair value	164,967	170,199
Subordinated Debt Securities [Member]
Amortized cost	32,300	32,300
Gross unrealized gains	3	356
Gross unrealized losses	(2,139)	(119)
Investment securities available for sale, at fair value	30,164	32,537
Taxable Municipal Bonds [Member]
Amortized cost	500	500
Gross unrealized gains	0	2
Gross unrealized losses	0	0
Investment securities available for sale, at fair value	500	502
Nontaxable Municipal Bonds [Member]
Amortized cost	151,896	122,877
Gross unrealized gains	49	4,307
Gross unrealized losses	(25,111)	(341)
Investment securities available for sale, at fair value	126,834	126,843
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	8,302	10,140
Gross unrealized gains	0	257
Gross unrealized losses	(833)	(80)
Investment securities available for sale, at fair value	$ 7,469	$ 10,317

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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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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