Note 7 - Loans (Details) - Components of Loans in Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Type of Loans:
Gross loans	$ 9,224,797	$ 8,914,080
Allowance for loan losses	(156,089)	(161,420)
Unamortized deferred loan fees	(11,116)	(12,392)
Total loans, net	9,057,592us-gaap_LoansReceivableNet	8,740,268us-gaap_LoansReceivableNet
Loans held for sale		973us-gaap_LoansReceivableHeldForSaleNet
Commercial Loans [Member]
Type of Loans:
Gross loans	2,434,550	2,382,493
Residential Mortgage Loans [Member]
Type of Loans:
Gross loans	1,600,269	1,570,059
Commercial Mortgage Loans [Member]
Type of Loans:
Gross loans	4,663,051	4,486,443
Equity Lines [Member]
Type of Loans:
Gross loans	175,997	172,879
Real Estate Construction Loans [Member]
Type of Loans:
Gross loans	345,560	298,654
Installment And Other Loans [Member]
Type of Loans:
Gross loans	$ 5,370	$ 3,552

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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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-Name Staff Accounting Bulletin (SAB)

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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.

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Amount classified as loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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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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