Note 10 - Fair Value Measurements - Carrying Value and Estimated Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Available for sale securities	$ 55,135	$ 58,012
Reported Value Measurement [Member]
Cash and cash equivalents	2,393	11,813
Available for sale securities	55,135	58,012
Loans held for sale		109
Loans	193,057	171,355
Accrued interest receivable	821	782
Cash value of life insurance	6,653	6,558
FHLB stock	1,098	514
Deposits	166,334	182,913
Advance payments by borrowers for taxes and insurance	812	36
FHLB advances	38,000	12,750
Accrued interest payable	360	37
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	2,393	11,813
Available for sale securities
Loans held for sale
Loans
Accrued interest receivable	821	782
Cash value of life insurance
FHLB stock
Deposits	99,104	106,125
Advance payments by borrowers for taxes and insurance	812	36
FHLB advances
Accrued interest payable	360	37
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Available for sale securities	55,135	58,012
Loans held for sale		109
Loans
Accrued interest receivable
Cash value of life insurance
FHLB stock
Deposits
Advance payments by borrowers for taxes and insurance
FHLB advances
Accrued interest payable
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Available for sale securities
Loans held for sale
Loans	193,014	171,729
Accrued interest receivable
Cash value of life insurance	6,653	6,558
FHLB stock	1,098	514
Deposits	66,797	76,099
Advance payments by borrowers for taxes and insurance
FHLB advances	37,736	12,597
Accrued interest payable

Fair value portion of accrued interest payable.

No definition available.

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- Definition

Fair value portion of accrued interest receivable.

+ References

No definition available.

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- Definition

Fair value portion of advance payments by borrowers for taxes and insurance.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ 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.

+ Details

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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=6876686&loc=d3e534808-122878

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- Definition

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

+ References

No definition available.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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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