Note 6 - Loans Receivable, Net and Allowance for Loan Losses - Changes in the Allowance for Loan Losses and Recorded Investment in Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Allowance for loan losses, beginning balance	$ 6,540	$ 3,746	$ 5,262	$ 3,061	$ 3,061
Charge-offs	(54)	0	(54)	(17)	(17)
Recoveries	0	0	0	0	17
Provision	655	557	1,933	1,259	2,201
Allowance for loan losses, ending balance	7,141	4,303	7,141	4,303	5,262
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	7,141	4,303	7,141	4,303	5,262
Ending balance:	587,701		587,701		411,866
Loans receivable, individually evaluated for impairment	1,846		1,846		140
Loans receivable, collectively evaluated for impairment	585,855		585,855		411,726
Real Estate Portfolio Segment [Member]
Ending balance:	449,565		449,565		282,246
Real Estate Portfolio Segment [Member] \| One-to-four Family Residential Owner Occupied Loans [Member]
Allowance for loan losses, beginning balance	104	72	73	88	88
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	15	0	46	(16)	(15)
Allowance for loan losses, ending balance	119	72	119	72	73
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	119	72	119	72	73
Ending balance:	17,424		17,424		9,779
Loans receivable, individually evaluated for impairment	0		0
Loans receivable, collectively evaluated for impairment	17,424		17,424		9,779
Real Estate Portfolio Segment [Member] \| One-to-four Family Residential Non-owner Occupied Loans [Member]
Allowance for loan losses, beginning balance	276	356	292	362	362
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	7	22	(9)	16	(70)
Allowance for loan losses, ending balance	283	378	283	378	292
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	283	378	283	378	292
Ending balance:	39,410		39,410		38,752
Loans receivable, individually evaluated for impairment	8		8		9
Loans receivable, collectively evaluated for impairment	39,402		39,402		38,743
Real Estate Portfolio Segment [Member] \| Multi-family (Five Or More) Residential Loans [Member]
Allowance for loan losses, beginning balance	377	242	249	229	229
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	90	5	218	18	20
Allowance for loan losses, ending balance	467	247	467	247	249
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	467	247	467	247	249
Ending balance:	48,468		48,468		29,344
Loans receivable, individually evaluated for impairment	1,708		1,708		0
Loans receivable, collectively evaluated for impairment	46,760		46,760		29,344
Real Estate Portfolio Segment [Member] \| Commercial Real Estate and Lines of Credit [Member]
Allowance for loan losses, beginning balance	3,383	1,617	2,475	1,287	1,287
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	187	407	1,095	737	1,188
Allowance for loan losses, ending balance	3,570	2,024	3,570	2,024	2,475
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	3,570	2,024	3,570	2,024	2,475
Ending balance:	313,160		313,160		183,822
Loans receivable, individually evaluated for impairment	130		130		131
Loans receivable, collectively evaluated for impairment	313,030		313,030		183,691
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Allowance for loan losses, beginning balance	283	163	119	62	62
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	(76)	(28)	88	73	57
Allowance for loan losses, ending balance	207	135	207	135	119
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	207	135	207	135	119
Ending balance:	25,838		25,838		15,843
Loans receivable, individually evaluated for impairment	0		0		0
Loans receivable, collectively evaluated for impairment	25,838		25,838		15,843
Real Estate Portfolio Segment [Member] \| Home Equity Loan [Member]
Allowance for loan losses, beginning balance	32	26	29	20	20
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	3	(4)	6	2	9
Allowance for loan losses, ending balance	35	22	35	22	29
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	35	22	35	22	29
Ending balance:	5,265		5,265		4,706
Loans receivable, individually evaluated for impairment	0		0		0
Loans receivable, collectively evaluated for impairment	5,265		5,265		4,706
Commercial and Consumer Portfolio Segments [Member]
Allowance for loan losses, beginning balance	1,735	970	1,625	763	763
Charge-offs	(54)	0	(54)	(17)	(17)
Recoveries	0	0	0	0	17
Provision	379	205	489	429	862
Allowance for loan losses, ending balance	2,060	1,175	2,060	1,175	1,625
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	2,060	1,175	2,060	1,175	1,625
Ending balance:	138,136		138,136		129,620
Loans receivable, individually evaluated for impairment	0		0		0
Loans receivable, collectively evaluated for impairment	138,136		138,136		129,620
Unallocated Financing Receivables [Member]
Allowance for loan losses, beginning balance	350	300	400	250	250
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision	50	(50)	0	0	150
Allowance for loan losses, ending balance	400	250	400	250	400
Allowance for loan losses, individually evaluated for impairment	0	0	0	0	0
Allowance for loan losses, collectively evaluated for impairment	400	$ 250	400	$ 250	400
Ending balance:
Loans receivable, individually evaluated for impairment
Loans receivable, collectively evaluated for impairment

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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