Note 11 - Deposits (Details) - Deposit Composition and Interest Rate - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deposit Composition and Interest Rate [Abstract]
Noninterest bearing demand	$ 1,405,067	$ 1,175,799	$ 849,409
Interest bearing transaction	$ 178,797	$ 143,628	$ 118,580
Interest bearing transaction	0.16%	0.13%	0.26%
Savings and money market	$ 2,835,325	$ 2,302,600	$ 1,811,088
Savings and money market	0.34%	0.32%	0.35%
Time, $100,000 or more	$ 406,570	$ 393,132	$ 203,706
Time, $100,000 or more	0.77%	0.68%	0.88%
Other time	$ 332,685	$ 295,609	$ 242,631
Other time	0.74%	0.70%	0.54%
Total	$ 5,158,444	$ 4,310,768	$ 3,225,414

No definition available.

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts. Includes deposits in savings accounts.

+ References

No definition available.

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- Definition

The weighted average rate for interest bearing transaction deposits.

+ References

No definition available.

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- Definition

The weighted average rate for savings and money market deposits.

+ References

No definition available.

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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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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

+ References

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- Definition

The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph A
-Subparagraph 4

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- Definition

The aggregate amount of domestic or foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000.

+ References

No definition available.

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- Definition

The weighted average interest rate of all domestic and foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more, at the balance sheet date.

+ References

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- Definition

The weighted average interest rate of domestic and foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more, with maturities of three months or less.

+ References

No definition available.

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