Note 10 - Hedging Activities (Details) (USD $)	1 Months Ended
Feb. 29, 2012	Mar. 31, 2015	Dec. 31, 2014
Note 10 - Hedging Activities (Details) [Line Items]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust	$ 32,000,000	$ 54,642,000	$ 54,472,000
Fair Value of Interest Rate Swap Agreement Liability		500,000	300,000
London Interbank Offered Rate (LIBOR) [Member] \| Junior Subordinated Debt [Member]
Note 10 - Hedging Activities (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.18%
Derivative, Notional Amount	$ 32,000,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Fair value disclosure of the liability related to a derivative interest rate swap agreement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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