Note 2 - Investment Securities - Amortized Cost and Estimated Fair Value of Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost	$ 242,461	$ 647,557
Gross unrealized gains	0	742
Gross unrealized losses	41,139	16,464
Fair value	201,322	631,835
US Government Agencies Debt Securities [Member]
Amortized cost		4,969
Gross unrealized gains		0
Gross unrealized losses		269
Fair value		4,700
Collateralized Mortgage-Backed Securities [Member]
Amortized cost	107,055	411,729
Gross unrealized gains	0	42
Gross unrealized losses	10,083	12,180
Fair value	96,972	399,591
State, County and Municipal [Member]
Amortized cost	134,906	230,359
Gross unrealized gains	0	700
Gross unrealized losses	30,993	4,008
Fair value	103,913	227,051
Other Debt Obligations [Member]
Amortized cost	500	500
Gross unrealized gains	0	0
Gross unrealized losses	63	7
Fair value	$ 437	$ 493

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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