Note 5 - Disclosures About Fair Value of Assets and Liabilities - Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Reported Value Measurement [Member]
Financial assets
Servicing rights	$ 802	$ 483
Cash and due from banks	1,208	1,419
Interest-earning demand deposits	2,011	8,438
Financial liabilities
Advances from the Federal Home Loan Bank	10,027	10,027
Accrued interest payable	15	7
Deposits	95,512	76,841
Federal funds sold	17,751	1,000
Interest-earning time deposits in banks	744	992
Loans, net	90,831	83,008
Federal Home Loan Bank stock	468	468
Accrued interest receivable	220	203
Estimate of Fair Value Measurement [Member]
Financial assets
Servicing rights	802	483
Cash and due from banks	1,208	1,419
Interest-earning demand deposits	2,011	8,438
Financial liabilities
Advances from the Federal Home Loan Bank	10,105	10,120
Accrued interest payable	15	7
Deposits	95,481	77,104
Federal funds sold	17,751	1,000
Interest-earning time deposits in banks	744	992
Loans, net	90,178	83,538
Federal Home Loan Bank stock	468	468
Accrued interest receivable	220	203
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets
Servicing rights
Cash and due from banks	1,208	1,419
Interest-earning demand deposits	2,011	8,438
Financial liabilities
Advances from the Federal Home Loan Bank
Accrued interest payable	15	7
Deposits	54,133	45,080
Federal funds sold	17,751	1,000
Interest-earning time deposits in banks
Loans, net
Federal Home Loan Bank stock
Accrued interest receivable	220	203
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets
Servicing rights
Cash and due from banks
Interest-earning demand deposits
Financial liabilities
Advances from the Federal Home Loan Bank	10,105	10,120
Accrued interest payable
Deposits	41,348	32,024
Federal funds sold
Interest-earning time deposits in banks	744	992
Loans, net
Federal Home Loan Bank stock	468	468
Accrued interest receivable
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets
Servicing rights	802	483
Cash and due from banks
Interest-earning demand deposits
Financial liabilities
Advances from the Federal Home Loan Bank
Accrued interest payable
Deposits
Federal funds sold
Interest-earning time deposits in banks
Loans, net	90,178	83,538
Federal Home Loan Bank stock
Accrued interest receivable

The fair value of accrued interest payable.

No definition available.

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- Definition

The fair value of accrued interest on loans.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of cash and cash due from banks.

+ References

No definition available.

+ Details

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- Definition

The fair value portion of interest-earning demand deposits.

+ References

No definition available.

+ Details

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- Definition

The fair value portion of interest-earning time deposits.

+ References

No definition available.

+ Details

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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 short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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 borrowing from Federal Home Loan Bank (FHLBank).

+ References

+ Details

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- References

No definition available.

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- References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75030709&loc=d3e39828-111592

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

+ Details

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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