Note 9 - Deposits (Details) - Time Deposit Maturities (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Other Time Deposits [Member}
Note 9 - Deposits (Details) - Time Deposit Maturities [Line Items]
Time deposits, maturities, year one	$ 772,529
Time deposits, maturities, year two	162,465
Time deposits, maturities, year three	109,302
Time deposits, maturities, year four	116,420
Time deposits, maturities, year five	1,820
Time deposits, maturities, after year five	11
Time deposits, maturities, total	1,162,547
Total Time Deposits [Member]
Note 9 - Deposits (Details) - Time Deposit Maturities [Line Items]
Time deposits, maturities, year one	3,373,672
Time deposits, maturities, year two	325,513
Time deposits, maturities, year three	347,635
Time deposits, maturities, year four	178,412
Time deposits, maturities, year five	42,485
Time deposits, maturities, after year five	11
Time deposits, maturities, total	4,267,728
Time Deposits 100000 Dollars and Over [Member]
Note 9 - Deposits (Details) - Time Deposit Maturities [Line Items]
Time deposits, maturities, year one	2,601,143
Time deposits, maturities, year two	163,048
Time deposits, maturities, year three	238,333
Time deposits, maturities, year four	61,992
Time deposits, maturities, year five	40,665
Time deposits, maturities, total	$ 3,105,181

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Amount of time deposits maturing after 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

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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

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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.

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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.

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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.

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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.

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Any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time. Because of their short-term, time deposits are considered highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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