Note 5 - Allowances for Loan Losses - Troubled Debt Restructurings (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of Loans	5	3
Troubled debt restructurings, accrual status	$ 7,869	$ 5,897
Troubled debt restructurings, non-accrual status	349	349
Troubled debt restructurings	$ 8,218	$ 6,246
Commercial Real Estate Portfolio Segment [Member]
Number of Loans	1	1
Troubled debt restructurings, accrual status	$ 6,452	$ 5,669
Troubled debt restructurings, non-accrual status
Troubled debt restructurings	$ 6,452	$ 5,669
Construction and Land Development Portfolio Segment [Member]
Number of Loans
Troubled debt restructurings, accrual status
Troubled debt restructurings, non-accrual status
Troubled debt restructurings
Commercial Portfolio Segment [Member]
Number of Loans	3	2
Troubled debt restructurings, accrual status	$ 1,175	$ 228
Troubled debt restructurings, non-accrual status	349	349
Troubled debt restructurings	$ 1,524	$ 577
Owner Occupied Real Estate [Member]
Number of Loans	1
Troubled debt restructurings, accrual status	$ 242
Troubled debt restructurings, non-accrual status
Troubled debt restructurings	$ 242
Consumer Portfolio Segment [Member]
Number of Loans
Troubled debt restructurings, accrual status
Troubled debt restructurings, non-accrual status
Troubled debt restructurings
Residential Portfolio Segment [Member]
Number of Loans
Troubled debt restructurings, accrual status
Troubled debt restructurings, non-accrual status
Troubled debt restructurings

Cumulative number of financing receivables that have been modified by troubled debt restructurings.

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- Definition

Recorded investment in financing receivables that have undergone troubled debt restructuring and are accruing.

+ References

No definition available.

+ Details

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- Definition

Recorded investment in financing receivables that have undergone troubled debt restructuring and are not accruing.

+ References

No definition available.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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