Note 3 - Acquisitions (Details Textual) - Acquisition of MNB [Member] $ in Millions	Oct. 01, 2015 USD ($) shares
Parent Company [Member]
Payments to Acquire Businesses, Gross	$ 10.1
Metropolitan National Bank [Member]
Payments to Acquire Businesses, Gross	17.9
Changes Measurement [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	450.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans, Net	365.0
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Deposits	$ 370.6
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Business Combination, Consideration Transferred	$ 70.0
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares \| shares	4,610,317
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 42.0
Payments to Acquire Businesses, Gross	$ 28.0

The aggregate of all deposit liabilities, assumed at the acquisition date.

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- Definition

The amount of loans, net of discounts, recognized as of the acquisition date.

+ References

No definition available.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Amount of assets acquired at the acquisition date.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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