Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	$ 8,565,278	$ 8,084,563
Allowance for loan losses	(169,077)	(173,889)
Unamortized deferred loan fees	(13,501)	(13,487)
Total loans, net	8,382,700	7,897,187
Commercial Loans [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	2,322,880	2,298,724
Residential Mortgage Loans [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	1,468,715	1,355,255
Commercial Mortgage Loans [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	4,308,170	4,023,051
Equity Lines [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	170,711	171,277
Real Estate Construction Loans [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	285,339	221,701
Installment And Other Loans [Member]
Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets [Line Items]
Gross Loans	$ 9,463	$ 14,555

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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-SubTopic 210

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 7

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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