Loans and Loans Held for Sale - Composition of Loans (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Composition of the loans
Commercial Loans	$ 2,660,260	$ 2,593,880
Consumer Loans	967,636	972,319
Total Portfolio Loans	3,627,896	3,566,199
Loans held for sale	1,133	2,136
Total Loans	3,629,029	3,568,335
Commercial Real Estate [Member]
Composition of the loans
Commercial Loans	1,607,958	1,607,756
Total Portfolio Loans	1,607,958	1,607,756
Commercial and Industrial [Member]
Composition of the loans
Commercial Loans	884,870	842,449
Total Portfolio Loans	884,870	842,449
Commercial Construction [Member]
Composition of the loans
Commercial Loans	167,432	143,675
Total Portfolio Loans	167,432	143,675
Residential Mortgage [Member]
Composition of the loans
Consumer Loans	490,120	487,092
Total Portfolio Loans	490,120	487,092
Home Equity [Member]
Composition of the loans
Consumer Loans	410,695	414,195
Total Portfolio Loans	410,695	414,195
Installment and Other Consumer [Member]
Composition of the loans
Consumer Loans	64,561	67,883
Total Portfolio Loans	64,561	67,883
Consumer Construction [Member]
Composition of the loans
Consumer Loans	2,260	3,149
Total Portfolio Loans	$ 2,260	$ 3,149

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Reflects the aggregate gross carrying amount of all commercial loans and leases held in portfolio, prior to deducting deferred income and the allowance for losses on commercial loans and leases.

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Reflects the aggregate gross carrying amount of all consumer loans and leases held in portfolio, prior to deducting deferred income and the allowance for losses on consumer loans and leases.

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Amount before allowance and after 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. Excludes loans and leases covered under loss sharing agreements.

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Amount of loans held for sale, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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

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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

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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