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Note 8 - Loans Receivable, Net - Loans Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Loans receivable	$ 863,397		$ 787,887
Unamortized discounts	15		13
Net deferred loan fees	655		519
Allowance for credit losses	11,967	$ 11,517	10,277	$ 10,141	$ 9,644	$ 9,279
Total loans receivable, net	850,760		777,078
Residential Portfolio Segment [Member]
Loans receivable	260,716		205,890
Allowance for credit losses	1,399	1,243	1,261	1,146	1,068	974
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	495,027		471,345
Allowance for credit losses	8,052	7,865	7,026	7,001	6,586	6,388
Consumer Portfolio Segment [Member]
Loans receivable	43,991		44,817
Allowance for credit losses	586	582	1,058	1,056	1,047	981
Commercial Portfolio Segment [Member]
Loans receivable	63,663		65,835
Allowance for credit losses	1,930	$ 1,827	932	$ 938	$ 943	$ 936
Single Family Segment [Member] \| Residential Portfolio Segment [Member]
Loans receivable	260,716		205,890
Real Estate [Member] \| Commercial Real Estate Portfolio Segment [Member]
Loans receivable	270,638		249,783
Commercial Real Estate Other [Member] \| Commercial Real Estate Portfolio Segment [Member]
Loans receivable	$ 224,389		$ 221,562