Loans and Loans Held for Sale - Composition of Loans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Composition of the loans
Total Portfolio Loans	$ 3,566,199	$ 3,346,622
Loans held for sale	2,136	22,499
Total Loans	3,568,335	3,369,121
Commercial Real Estate [Member]
Composition of the loans
Total Portfolio Loans	1,607,756	1,452,133
Commercial and Industrial [Member]
Composition of the loans
Total Portfolio Loans	842,449	791,396
Commercial Construction [Member]
Composition of the loans
Total Portfolio Loans	143,675	168,143
Total Commercial Loans [Member]
Composition of the loans
Total Portfolio Loans	2,593,880	2,411,672
Residential Mortgage [Member]
Composition of the loans
Total Portfolio Loans	487,092	427,303
Home Equity [Member]
Composition of the loans
Total Portfolio Loans	414,195	431,335
Installment and Other Consumer [Member]
Composition of the loans
Total Portfolio Loans	67,883	73,875
Consumer Construction [Member]
Composition of the loans
Total Portfolio Loans	3,149	2,437
Total Consumer Loans [Member]
Composition of the loans
Total Portfolio Loans	$ 972,319	$ 934,950