Note 12 - Other Liabilities FHLB Advances (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
FHLB Advances [Line Items]
FHLB advances	$ 115,308	$ 0
Federal Home Loan Bank, Advances, Weighted Average Interest Rate	2.21%
Federal Home Loan Bank, Advances, Maturity Period, Fixed Rate	90 days
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year	$ 102,800
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	6,500
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	6,000
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 122,800
Minimum [Member]
FHLB Advances [Line Items]
Federal Home Loan Bank, Ratio of Market Value of Collateral to Advances	1.03
Maximum [Member]
FHLB Advances [Line Items]
Federal Home Loan Bank, Ratio of Market Value of Collateral to Advances	1.05

[Line Items] for FHLB Advances [Table]

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- Definition

The ratio of the market value of the collateralized eligible assets to the principal balance of the FHLB advances

+ References

No definition available.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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