Note 6 - Other Real Estate Owned (Details) - Activity in the Valuation Allowance for Other Real Estate Losses (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Activity in the Valuation Allowance for Other Real Estate Losses [Abstract]
Balance, beginning of year	$ 13,384	$ 19,556	$ 26,422
Provision/(Reversal) for losses	1,619	(2,122)	10,668
OREO disposal	(12,893)us-gaap_RealEstateCostOfRealEstateSold	(4,050)us-gaap_RealEstateCostOfRealEstateSold	(17,534)us-gaap_RealEstateCostOfRealEstateSold
Balance, end of year	$ 2,110	$ 13,384	$ 19,556

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Data Type:	xbrli:stringItemType
Balance Type:	na
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Amount of real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule III)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 970

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-28.4)

-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

+ 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 210.9-03.10(4))

-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 10

-Subparagraph 4

-Article 9

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of expense recognized in the income statement for a decrease in valuation of real estate owned (REO).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration