Note 8 - Deposits (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Time Deposits, at or Above FDIC Insurance Limit	$ 214,000	$ 169,200
Interest-bearing Domestic Deposit, Brokered	1,114,900	982,800
Deposits	4,205,631	3,892,547
Letter of Credit Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	382,500
Government Deposits [Member]
Deposits	1,062,100	975,900
Government Deposits [Member] \| ICS Deposits [Member]
Deposits	539,000	210,700
Government Deposits [Member] \| Collateralized Deposits [Member]
Deposits	523,100	765,200
Government Deposits [Member] \| Securities Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	218,800	364,700
Government Deposits [Member] \| Letter of Credit Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	$ 382,500	$ 494,000

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ 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

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Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

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