Note 2 - Securities Available for Sale - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Amortized cost	$ 222,639	$ 179,884
Gross unrealized gains	98	2,322
Gross unrealized losses	(25,439)	(3,190)
Fair value	197,298	179,016
Securities available for sale (at fair value)	197,298	179,016
Collateralized Mortgage-Backed Securities [Member]
Amortized cost	15,735	19,133
Gross unrealized gains	3	542
Gross unrealized losses	(1,821)	(187)
Fair value	13,917	19,488
Securities available for sale (at fair value)	13,917	19,488
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	147,192	100,543
Gross unrealized gains	0	503
Gross unrealized losses	(19,144)	(1,744)
Fair value	128,048	99,302
Securities available for sale (at fair value)	128,048	99,302
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Amortized cost	9,299	2,913
Gross unrealized gains	0	30
Gross unrealized losses	(867)	0
Fair value	8,432	2,943
Securities available for sale (at fair value)	8,432	2,943
Mortgage-related Securities [Member]
Amortized cost	172,226	122,589
Gross unrealized gains	3	1,075
Gross unrealized losses	(21,832)	(1,931)
Fair value	150,397	121,733
Securities available for sale (at fair value)	150,397	121,733
US Government-sponsored Enterprises Debt Securities [Member]
Amortized cost	2,500	2,500
Gross unrealized gains	0	0
Gross unrealized losses	(258)	(52)
Fair value	2,242	2,448
Securities available for sale (at fair value)	2,242	2,448
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	35,358	42,295
Gross unrealized gains	95	1,206
Gross unrealized losses	(1,995)	(7)
Fair value	33,458	43,494
Securities available for sale (at fair value)	33,458	43,494
Other Debt Obligations [Member]
Amortized cost	12,500	12,500
Gross unrealized gains	0	41
Gross unrealized losses	(1,354)	(1,200)
Fair value	11,146	11,341
Securities available for sale (at fair value)	11,146	11,341
Debt Securities [Member]
Amortized cost	50,358	57,295
Debt [Member]
Gross unrealized gains	95	1,247
Gross unrealized losses	(3,607)	(1,259)
Fair value	46,846	57,283
Securities available for sale (at fair value)	46,846	$ 57,283
Other Securities [Member]
Amortized cost	55
Gross unrealized gains	0
Gross unrealized losses	0
Fair value	55
Securities available for sale (at fair value)	$ 55

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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