Note 9 - Fair Value of Financial Instruments - Quantitative Information About Non-recurring Level 3 Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Trust Preferred Securities [Member]
Fair Value	$ 1,083	$ 7,191
Valuation Technique	Discounted cash flows	Discounted cash flows
Unobservable Input	Discount rate	Discount rate
Range		7.00%
Trust Preferred Securities [Member] \| Minimum [Member]
Range		6.30%
Trust Preferred Securities [Member] \| Weighted Average [Member]
Range	5.90%
Trust Preferred Securities [Member] \| Maximum [Member]
Range		7.10%
Junior Subordinated Debentures [Member]
Valuation Technique	Discounted cash flows	Discounted cash flows
Unobservable Input	Discount rate	Discount rate
Range		6.30%
Fair Value	$ 36,071	$ 33,959
Junior Subordinated Debentures [Member] \| Weighted Average [Member]
Range	5.90%

Interest rate of the unobservable input to the valuation technique.

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- Definition

Unobservable input of the valuation technique.

+ References

No definition available.

+ Details

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- Definition

Fair value of 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)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

+ Details

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- Definition

Description of the inputs and valuation technique(s) used 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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