Note 7 - Securities Available for Sale - Summary of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Securities available for sale, amortized cost	$ 282,196	$ 287,966
Investment securities available for sale, gross unrealized gains	0	734
Investment securities available for sale, gross unrealized losses	(32,984)	(2,935)
Securities available for sale	249,212	285,765
Mortgage Backed Securities, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	123,246	138,628
Investment securities available for sale, gross unrealized gains	0	550
Investment securities available for sale, gross unrealized losses	(16,195)	(1,367)
Securities available for sale	107,051	137,811
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal Home Loan Mortgage Corporation Certificates and Obligations FHLMC [Member]
Securities available for sale, amortized cost	103,213	108,599
Investment securities available for sale, gross unrealized gains	0	126
Investment securities available for sale, gross unrealized losses	(14,349)	(1,189)
Securities available for sale	88,864	107,536
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	40	48
Investment securities available for sale, gross unrealized gains	0	2
Investment securities available for sale, gross unrealized losses	(3)	0
Securities available for sale	37	50
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale, amortized cost	226,499	247,275
Investment securities available for sale, gross unrealized gains	0	678
Investment securities available for sale, gross unrealized losses	(30,547)	(2,556)
Securities available for sale	195,952	245,397
Other Marketable Securities, Us Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	54,997	39,991
Investment securities available for sale, gross unrealized gains	0	56
Investment securities available for sale, gross unrealized losses	(2,262)	(337)
Securities available for sale	52,735	39,710
Other Marketable Securities, Corporate Preferred Stock [Member]
Securities available for sale, amortized cost	700	700
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(175)	(42)
Securities available for sale	525	658
Other Marketable Securities [Member]
Securities available for sale, amortized cost	55,697	40,691
Investment securities available for sale, gross unrealized gains	0	56
Investment securities available for sale, gross unrealized losses	(2,437)	(379)
Securities available for sale	$ 53,260	$ 40,368

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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