Note 4 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized cost	$ 165,817	$ 108,937
Gross unrealized gains	4,922	5,435
Gross unrealized losses	(540)	(12)
Investment securities available for sale, at fair value	170,199	114,360
Subordinated Debt Securities [Member]
Amortized cost	32,300	21,050
Gross unrealized gains	356	254
Gross unrealized losses	(119)	(7)
Investment securities available for sale, at fair value	32,537	21,297
Taxable Municipal Bonds [Member]
Amortized cost	500	500
Gross unrealized gains	2	2
Gross unrealized losses	0	0
Investment securities available for sale, at fair value	502	502
Nontaxable Municipal Bonds [Member]
Amortized cost	122,877	73,157
Gross unrealized gains	4,307	4,643
Gross unrealized losses	(341)	0
Investment securities available for sale, at fair value	126,843	77,800
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	10,140	14,230
Gross unrealized gains	257	536
Gross unrealized losses	(80)	(5)
Investment securities available for sale, at fair value	$ 10,317	$ 14,761

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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