Loans and Leases Outstanding (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 1,284	$ 3,412
Real estate loans	1,141,105	1,056,339
Commercial and industrial	303,259	291,620
Consumer	17,572	17,666
Leases	38,079	32,831
Total	1,500,015	1,398,456
Total loans and leases	1,501,299	1,401,868
Loans with predetermined rates	814,781	723,417
Loans with adjustable or floating rates	686,518	678,451
Total loans and leases	1,501,299	1,401,868
Net deferred loan origination costs included in the above loan table	449	402
Commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans	622,771	546,358
Total	622,771	546,358
Home equity lines and loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans	187,634	194,861
Total	187,634	194,861
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans	291,645	288,212
Total	291,645	288,212
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans	39,055	26,908
Total	$ 39,055	$ 26,908

Loans And Leases Deferred Origination Costs

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The aggregate amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or have been elected at fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

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Amount before allowance of consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. 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 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 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. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount before allowance of other loans and leases not otherwise specified in the taxonomy. 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 before allowance of loans issued to commercial and industrial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes real estate loans and loans covered under loss sharing agreements.

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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.

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Amount of loan with fixed rate of interest.

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Amount of loan with variable or adjustable rate of interest.

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Total carrying amount of mortgage loans as of the balance sheet date.

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