Note 11 - Fair Value Measurements and Fair Values of Financial Instruments - Financial Assets and Liabilities on a Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Investment securities available for sale	$ 2,836	$ 2,970
Fair Value, Recurring [Member]
Investment securities available for sale	2,836	2,970
Total fair value measurements	2,836	2,970
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale	0	0
Total fair value measurements	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale	2,836	2,970
Total fair value measurements	2,836	2,970
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale	0	0
Total fair value measurements	0	0
Fair Value, Nonrecurring [Member]
Total fair value measurements	1,577	1,860
Impaired loans		1,860
Fair Value, Nonrecurring [Member] \| Nonperforming Financial Instruments [Member]
Collateral-dependent loans	1,577
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total fair value measurements	0	0
Impaired loans		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Nonperforming Financial Instruments [Member]
Collateral-dependent loans	0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total fair value measurements	0	0
Impaired loans		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Nonperforming Financial Instruments [Member]
Collateral-dependent loans	0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total fair value measurements	1,577	1,860
Impaired loans		1,860
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Nonperforming Financial Instruments [Member]
Collateral-dependent loans	1,577
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Government National Mortgage Association (GNMA) [Member]
Investment securities available for sale	2,740	2,871
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Government National Mortgage Association (GNMA) [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale	2,740	2,871
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Government National Mortgage Association (GNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Government National Mortgage Association (GNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale	2,740	2,871
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Government National Mortgage Association (GNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association (FNMA) [Member]
Investment securities available for sale	96	99
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association (FNMA) [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale	96	99
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association (FNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association (FNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale	96	99
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association (FNMA) [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale	$ 0	$ 0

Fair value disclosure of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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