Note 9 - Fair Value Measurements and Disclosures (Details Textual)	9 Months Ended
Sep. 30, 2016 USD ($) security	Dec. 31, 2015 USD ($)
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Loss Severity	95.00%
Minimum Cost Saving for Refinance	2.00%
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 1,763,000	$ 2,527,000
Partial Charge-offs [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 0	$ 145,000
Collateralized Debt Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Number Of Trust Preferred Securities \| security	6
Fair Value, Inputs, Level 3 [Member] \| Collateralized Debt Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Number Of Trust Preferred Securities \| security	6
Maximum [Member] \| Collateralized Debt Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Loss Severity	100.00%
Minimum [Member] \| Collateralized Debt Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Loss Severity	0.00%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ 0
Fair Value Inputs, Loss Severity	95.00%
Minimum Cost Saving for Refinance	2.00%
Debt Instrument, Basis Spread on Variable Rate	7.79%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Instrument, Basis Spread on Variable Rate	5.03%

The least percentage of cost been saved during the process of refinancing.

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- Definition

The number of trust preferred securities held by the entity.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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- Definition

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+ References

No definition available.

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- Definition

Loss, including interest and principal, incurred on a defaulted security, expressed as a percentage of the original principal balance, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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