Note 9 - Fair Value of Assets and Liabilities - Carrying Amounts and Fair Values of the Company's Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Reported Value Measurement [Member]
Cash and cash equivalents	$ 48,633	$ 27,815
Net loans	528,101	514,251
Bank-owned life insurance	21,046	17,768
Accrued interest receivable	2,471	2,336
Securities sold under agreements to repurchase	1,088	1,922
Federal Home Loan Bank advances - short term	7,000	0
Federal Home Loan Bank advances - long term	24,000	24,000
Subordinated debt	5,155	5,155
Accrued interest payable	411	510
Reported Value Measurement [Member] \| Demand, Savings and Money Market Deposits [Member]
Demand, savings and money market deposits	571,060	476,358
Reported Value Measurement [Member] \| Time Deposits [Member]
Demand, savings and money market deposits	109,580	142,023
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	48,633	27,815
Net loans	530,052	517,787
Bank-owned life insurance	21,046	17,768
Accrued interest receivable	2,471	2,336
Securities sold under agreements to repurchase	1,088	1,922
Federal Home Loan Bank advances - short term	7,002	0
Federal Home Loan Bank advances - long term	24,472	24,005
Subordinated debt	4,537	4,835
Accrued interest payable	411	510
Estimate of Fair Value Measurement [Member] \| Demand, Savings and Money Market Deposits [Member]
Demand, savings and money market deposits	571,060	476,358
Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Demand, savings and money market deposits	110,833	143,485
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	48,633	27,815
Net loans	0	0
Bank-owned life insurance	21,046	17,768
Accrued interest receivable	2,471	2,336
Securities sold under agreements to repurchase	1,088	1,922
Federal Home Loan Bank advances - short term	0	0
Federal Home Loan Bank advances - long term	0	0
Subordinated debt	0	0
Accrued interest payable	411	510
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Demand, Savings and Money Market Deposits [Member]
Demand, savings and money market deposits	571,060	476,358
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Time Deposits [Member]
Demand, savings and money market deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Net loans	0	0
Bank-owned life insurance	0	0
Accrued interest receivable	0	0
Securities sold under agreements to repurchase	0	0
Federal Home Loan Bank advances - short term	0	0
Federal Home Loan Bank advances - long term	0	0
Subordinated debt	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Demand, Savings and Money Market Deposits [Member]
Demand, savings and money market deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Time Deposits [Member]
Demand, savings and money market deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Net loans	530,052	517,787
Bank-owned life insurance	0	0
Accrued interest receivable	0	0
Securities sold under agreements to repurchase	0	0
Federal Home Loan Bank advances - short term	7,002	0
Federal Home Loan Bank advances - long term	24,472	24,005
Subordinated debt	4,537	4,835
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Demand, Savings and Money Market Deposits [Member]
Demand, savings and money market deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Time Deposits [Member]
Demand, savings and money market deposits	$ 110,833	$ 143,485

The fair value portion of accrued interest payable.

No definition available.

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- Definition

The fair value portion of accrued interest receivable.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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 the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ 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 of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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