Note 3 - Loans Receivable - Impaired Loans by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Recorded investment, with no allowance recorded	$ 309	$ 1,764
Unpaid principal balance, with no allowance recorded	584	2,196
Average recorded investment, with no allowance recorded	1,390	1,718
Interest income recognized, with no allowance recorded	20	60
Recorded investment, with an allowance recorded	2,886	3,747
Unpaid principal balance, with an allowance recorded	3,108	4,139
Related allowance	113	317
Average recorded investment, with an allowance recorded	3,234	4,660
Interest income recognized, with an allowance recorded	161	225
Recorded investment, total	3,195	5,511
Unpaid principal balance, total	3,692	6,335
Average recorded investment, total	4,624	6,378
Interest income recognized, total	181	285
Real Estate Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Recorded investment, with no allowance recorded	212	227
Unpaid principal balance, with no allowance recorded	247	257
Average recorded investment, with no allowance recorded	219	168
Interest income recognized, with no allowance recorded	12	13
Recorded investment, with an allowance recorded	2,045	2,739
Unpaid principal balance, with an allowance recorded	2,245	2,941
Related allowance	25	36
Average recorded investment, with an allowance recorded	2,281	3,197
Interest income recognized, with an allowance recorded	138	177
Recorded investment, total	2,257	2,966
Unpaid principal balance, total	2,492	3,198
Average recorded investment, total	2,500	3,365
Interest income recognized, total	150	190
Real Estate Portfolio Segment [Member] \| Multi-family Loan [Member]
Recorded investment, with no allowance recorded	0	0
Unpaid principal balance, with no allowance recorded	0	0
Average recorded investment, with no allowance recorded	94	119
Interest income recognized, with no allowance recorded	0	0
Recorded investment, with an allowance recorded	0	284
Unpaid principal balance, with an allowance recorded	0	284
Related allowance	0	0
Average recorded investment, with an allowance recorded	0	338
Interest income recognized, with an allowance recorded	0	0
Recorded investment, total	0
Unpaid principal balance, total	0
Average recorded investment, total	94
Interest income recognized, total	0
Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member]
Recorded investment, with no allowance recorded	71	1,216
Unpaid principal balance, with no allowance recorded	177	1,308
Average recorded investment, with no allowance recorded	1,016	1,213
Interest income recognized, with no allowance recorded	0	33
Recorded investment, with an allowance recorded	0	62
Unpaid principal balance, with an allowance recorded	0	62
Related allowance	0	1
Average recorded investment, with an allowance recorded	121	301
Interest income recognized, with an allowance recorded	0	3
Recorded investment, total	71	1,278
Unpaid principal balance, total	177	1,370
Average recorded investment, total	1,137	1,514
Interest income recognized, total	0	36
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment, with no allowance recorded	0	0
Unpaid principal balance, with no allowance recorded	24	29
Average recorded investment, with no allowance recorded	0	9
Interest income recognized, with no allowance recorded	0	0
Recorded investment, with an allowance recorded	22	26
Unpaid principal balance, with an allowance recorded	22	26
Related allowance	0	0
Average recorded investment, with an allowance recorded	24	27
Interest income recognized, with an allowance recorded	1	3
Recorded investment, total	22	26
Unpaid principal balance, total	46	55
Average recorded investment, total	24	36
Interest income recognized, total	1	3
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment, with no allowance recorded	26	37
Unpaid principal balance, with no allowance recorded	59	94
Average recorded investment, with no allowance recorded	32	41
Interest income recognized, with no allowance recorded	1	1
Recorded investment, with an allowance recorded	307	98
Unpaid principal balance, with an allowance recorded	329	157
Related allowance	5	4
Average recorded investment, with an allowance recorded	155	186
Interest income recognized, with an allowance recorded	9	9
Recorded investment, total	333	135
Unpaid principal balance, total	388	251
Average recorded investment, total	187	227
Interest income recognized, total	10	10
Consumer Portfolio Segment [Member] \| Automobile and Other Loan [Member]
Recorded investment, with no allowance recorded	0	0
Unpaid principal balance, with no allowance recorded	77	224
Average recorded investment, with no allowance recorded	29	0
Interest income recognized, with no allowance recorded	7	13
Recorded investment, with an allowance recorded	512	822
Unpaid principal balance, with an allowance recorded	512	953
Related allowance	83	276
Average recorded investment, with an allowance recorded	653	721
Interest income recognized, with an allowance recorded	13	33
Recorded investment, total	512	822
Unpaid principal balance, total	589	1,177
Average recorded investment, total	682	721
Interest income recognized, total	20	46
Commercial Portfolio Segment [Member]
Recorded investment, with no allowance recorded	0	0
Unpaid principal balance, with no allowance recorded	0	0
Average recorded investment, with no allowance recorded	0	68
Interest income recognized, with no allowance recorded	0	0
Recorded investment, with an allowance recorded	0	0
Unpaid principal balance, with an allowance recorded	0	0
Related allowance	0	0
Average recorded investment, with an allowance recorded	0	109
Interest income recognized, with an allowance recorded	0	0
Recorded investment, total	0	0
Unpaid principal balance, total	0	0
Average recorded investment, total	0	177
Interest income recognized, total	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 17
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