Note 8 - Deposits (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Time Deposits, at or Above FDIC Insurance Limit	$ 366,700	$ 238,800
Interest-bearing Domestic Deposit, Brokered	301,700	1,090,000
Reciprocal Deposits	685,300	682,400
Deposits, Total	4,960,784	4,383,278
Letter of Credit Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	659,600	402,100
Government Deposits [Member]
Deposits, Total	1,339,700	1,133,300
Government Deposits [Member] \| ICS Deposits [Member]
Deposits, Total	661,500	639,500
Government Deposits [Member] \| Collateralized Deposits [Member]
Deposits, Total	678,200	493,800
Government Deposits [Member] \| Debt Securities Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	178,900	183,900
Government Deposits [Member] \| Letter of Credit Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	$ 659,600	$ 402,100

Represents the amount of reciprocal deposits.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

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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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-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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