Note 7 - Loans (Detail) - Schedule of Components of Loans in Consolidated Balance Sheets (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Type of Loans:
Gross Loans	$ 6,908,544,000	$ 7,059,212,000
Allowance for loan losses	(194,743,000)	(206,280,000)
Unamortized deferred loan fees	(7,921,000)	(8,449,000)
Total loans, net	6,705,880,000	6,844,483,000
Loans held for sale	3,709,000	760,000
Commercial Loans Member
Type of Loans:
Gross Loans	1,844,849,000	1,868,275,000
Residential Mortgage Loans [Member]
Type of Loans:
Gross Loans	985,105,000	972,262,000
Commercial Mortgage Loans [Member]
Type of Loans:
Gross Loans	3,662,436,000	3,748,897,000
Equity Lines [Member]
Type of Loans:
Gross Loans	208,602,000	214,707,000
Real Estate Construction Loans [Member]
Type of Loans:
Gross Loans	188,081,000	237,372,000
Installment And Other Loans Member
Type of Loans:
Gross Loans	$ 19,471,000	$ 17,699,000

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Reflects the net amount of other additions and reductions in the reserve for credit losses.

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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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- Definition

The face amount of loans that will be sold to other entities.

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Total of loans held-for-sale and held-in-portfolio net of unearned income, allowance for loan and lease losses, if any, unamortized loan origination and other fees and costs, and purchased premiums or discounts.

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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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