Note 3 - Securities (Details) - Securities Held-to-maturity (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]
Securities held-to-maturity, amortized costs	$ 161,452	$ 163,983
Securities held-to-maturity, gross unrealized gains	7,225	3,304
Securities held-to-maturity, gross unrealized losses	974	7,950
Securities held-to-maturity, fair value	167,703	159,337
US Government Agencies Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held-to-maturity, amortized costs	18,922	13,973
Securities held-to-maturity, gross unrealized gains	350	280
Securities held-to-maturity, gross unrealized losses	245	1,448
Securities held-to-maturity, fair value	19,027	12,805
US States and Political Subdivisions Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held-to-maturity, amortized costs	140,702	149,490
Securities held-to-maturity, gross unrealized gains	6,823	2,971
Securities held-to-maturity, gross unrealized losses	727	6,502
Securities held-to-maturity, fair value	146,798	145,959
Collateralized Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held-to-maturity, amortized costs	415	520
Securities held-to-maturity, gross unrealized gains	51	53
Securities held-to-maturity, fair value	466	573
Corporate Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held-to-maturity, amortized costs	1,413
Securities held-to-maturity, gross unrealized gains	1
Securities held-to-maturity, gross unrealized losses	2
Securities held-to-maturity, fair value	$ 1,412

Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

+ References

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

No definition available.

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Fair value of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 50

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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