Note 4 - Allowance for Loan Losses - Allowance by Impairment Methodology and Loans by Impairment Methodology (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Beginning balance	$ 4,934	$ 5,009	$ 5,009
Charge-offs	(328)	(228)	(884)
Recoveries	78	165	359
Provision for (recovery of) loan losses	900		450
Ending balance	5,584	4,946	4,934
Individually evaluated for impairment, allowance	11	129	33
Collectively evaluated for impairment, allowance	5,573	4,817	4,901
Loans	581,867		574,346
Individually evaluated for impairment, loans	1,522	2,175	1,459
Collectively evaluated for impairment, loans	580,345	548,300	572,887
Real Estate 1 [Member] \| Construction and Land Development [Member]
Beginning balance	464	561	561
Charge-offs			(2)
Recoveries		50	50
Provision for (recovery of) loan losses	(3)	(6)	(145)
Ending balance	461	605	464
Individually evaluated for impairment, allowance		71	22
Collectively evaluated for impairment, allowance	461	534	442
Loans	40,279		43,164
Individually evaluated for impairment, loans	400	398	367
Collectively evaluated for impairment, loans	39,879	48,550	42,797
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member]
Beginning balance	776	895	895
Charge-offs		(49)	(58)
Recoveries	2	2	9
Provision for (recovery of) loan losses	298	(82)	(70)
Ending balance	1,076	766	776
Individually evaluated for impairment, allowance	11	23	11
Collectively evaluated for impairment, allowance	1,065	743	765
Loans	230,980		229,438
Individually evaluated for impairment, loans	667	990	630
Collectively evaluated for impairment, loans	230,313	216,537	228,808
Real Estate 1 [Member] \| Other Real Estate Loans [Member]
Beginning balance	2,296	2,160	2,160
Charge-offs			(27)
Recoveries	1		1
Provision for (recovery of) loan losses	347	115	162
Ending balance	2,644	2,275	2,296
Individually evaluated for impairment, allowance		35
Collectively evaluated for impairment, allowance	2,644	2,240	2,296
Loans	241,374		236,555
Individually evaluated for impairment, loans	455	787	462
Collectively evaluated for impairment, loans	240,919	220,609	236,093
Commercial and Industrial Loans [Member]
Beginning balance	562	464	464
Charge-offs	(68)		(2)
Recoveries	2	2	8
Provision for (recovery of) loan losses	215	26	92
Ending balance	711	492	562
Individually evaluated for impairment, allowance
Collectively evaluated for impairment, allowance	711	492	562
Loans	55,508		50,153
Individually evaluated for impairment, loans
Collectively evaluated for impairment, loans	55,508	46,045	50,153
Consumer and Other Loans [Member]
Beginning balance	836	929	929
Charge-offs	(260)	(179)	(795)
Recoveries	73	111	291
Provision for (recovery of) loan losses	43	(53)	411
Ending balance	692	808	836
Individually evaluated for impairment, allowance
Collectively evaluated for impairment, allowance	692	808	836
Loans	13,726		15,036
Individually evaluated for impairment, loans
Collectively evaluated for impairment, loans	$ 13,726	$ 16,559	$ 15,036

Represents the amount of provision (reduction in reserve) for loan losses during the period.

No definition available.

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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