Loans and Loans Held for Sale - Composition of Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Composition of the loans
Commercial Loans	$ 3,639,300	$ 2,892,522
Consumer Loans	1,159,198	976,224
Total Portfolio Loans	4,798,498	3,868,746
Loans held for sale	13,634	2,970
Total Loans	4,812,132	3,871,716
Commercial Real Estate [Member]
Composition of the loans
Commercial Loans	2,054,935	1,682,236
Total Portfolio Loans	2,054,935	1,682,236
Total Loans	2,054,935	1,682,236
Commercial and Industrial [Member]
Composition of the loans
Commercial Loans	1,239,382	994,138
Total Portfolio Loans	1,239,382	994,138
Total Loans	1,239,382	994,138
Construction Loans [Member]
Composition of the loans
Commercial Loans	344,983	216,148
Total Portfolio Loans	344,983	216,148
Total Loans	344,983	216,148
Residential Mortgage [Member]
Composition of the loans
Consumer Loans	599,502	489,586
Total Loans	599,502	489,586
Home Equity [Member]
Composition of the loans
Consumer Loans	457,813	418,563
Total Loans	457,813	418,563
Consumer Borrower [Member]
Composition of the loans
Consumer Loans	94,437	65,567
Total Loans	94,437	65,567
Consumer Construction [Member]
Composition of the loans
Consumer Loans	7,446	2,508
Total Loans	$ 7,446	$ 2,508

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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, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. 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.

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