Note 10 - Fair Values Measurement - Carrying Amount and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Securities available for sale	$ 198,657	$ 209,000
Reported Value Measurement [Member]
Cash and cash equivalents	33,148	30,203
Securities available for sale	198,657	209,000
Federal Home Loan Bank stock	6,837	6,237
Loans, net	952,411	917,895
Accrued interest receivable	4,219	4,257
Deposits	1,057,900	1,026,975
Federal Home Loan Bank advances	61,349	61,389
Junior subordinated debentures	21,000	21,000
Subordinated capital note	17,000	17,000
Senior Debt	5,000	5,000
Accrued interest payable	715	1,129
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	33,148	30,203
Securities available for sale	198,657	209,000
Federal Home Loan Bank stock
Loans, net	903,898	925,388
Accrued interest receivable	4,219	4,257
Deposits	1,060,005	1,027,433
Federal Home Loan Bank advances	61,357	61,395
Junior subordinated debentures	14,153	17,466
Subordinated capital note	16,095	17,003
Senior Debt	4,900	5,022
Accrued interest payable	715	1,129
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	33,148	30,203
Securities available for sale
Federal Home Loan Bank stock
Loans, net
Accrued interest receivable
Deposits	185,658	187,551
Federal Home Loan Bank advances
Junior subordinated debentures
Subordinated capital note
Senior Debt
Accrued interest payable
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Securities available for sale	198,657	209,000
Federal Home Loan Bank stock
Loans, net
Accrued interest receivable	993	1,118
Deposits	874,347	839,882
Federal Home Loan Bank advances	61,357	61,395
Junior subordinated debentures
Subordinated capital note
Senior Debt
Accrued interest payable	509	647
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Securities available for sale
Federal Home Loan Bank stock
Loans, net	903,898	925,388
Accrued interest receivable	3,226	3,139
Deposits
Federal Home Loan Bank advances
Junior subordinated debentures	14,153	17,466
Subordinated capital note	16,095	17,003
Senior Debt	4,900	5,022
Accrued interest payable	$ 206	$ 482

Represents the fair value of accrued interest payable.

No definition available.

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- Definition

Represents the fair value of accrued interest receivable.

+ References

No definition available.

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- Definition

Fair value of junior subordinated debt obligations.

+ References

No definition available.

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- Definition

The fair value of subordinated capital notes.

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No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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No definition available.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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