Note 8 - Deposits (Details) - Maturity Distribution for Certificate of Deposits (USD $)	Dec. 31, 2014	Dec. 31, 2013
Maturity Distribution for Certificate of Deposits [Abstract]
In one year or less	$ 368,163,000us-gaap_TimeDepositMaturitiesYearOne	$ 213,454,000us-gaap_TimeDepositMaturitiesYearOne
In one to two years	153,346,000us-gaap_TimeDepositMaturitiesYearTwo	80,138,000us-gaap_TimeDepositMaturitiesYearTwo
In two to three years	118,919,000us-gaap_TimeDepositMaturitiesYearThree	73,271,000us-gaap_TimeDepositMaturitiesYearThree
In three to four years	60,953,000us-gaap_TimeDepositMaturitiesYearFour	95,979,000us-gaap_TimeDepositMaturitiesYearFour
In four to five years	37,368,000us-gaap_TimeDepositMaturitiesYearFive	48,126,000us-gaap_TimeDepositMaturitiesYearFive
Total certificates of deposit	$ 738,749,000us-gaap_TimeDeposits	$ 510,968,000us-gaap_TimeDeposits

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Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

+ Details

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- Definition

Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ 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 210.9-03.12)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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