Note 4 - Loans and Allowance for Credit Losses (Details) - Changes in the accretable yield for purchased loans (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Changes in the accretable yield for purchased loans [Abstract]
Balance at the beginning of the period	$ 4,948	$ 9,990
Reclassification from nonaccretable difference	8,864	12,121
Accretion	(7,363)	(17,163)
Reduction in FDIC indemnification asset	5,759	13,207
(Increase) in interest income	(1,604)	(3,956)
Balance at the end of the period	$ 6,449	$ 4,948

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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- Definition

Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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The current period adjustment to accretion for FDIC indemnification offset. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The current period net recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan, less the current period adjustment related to FDIC indemnification offset. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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