Noninterest Income and Expenses - Summary of Noninterest Income and Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
NONINTEREST INCOME
Service charges on deposit accounts	$ 6,711	$ 6,245	$ 6,262
Trust fees	2,711	2,279	2,111
Mortgage banking fees	4,173	3,710	2,140
Brokerage commissions and fees	1,631	1,071	1,122
Marine finance fees	1,189	1,111	1,209
Interchange income	5,404	4,501	3,808
Other deposit based EFT fees	342	336	318
Other	2,158	2,191	1,375
Noninterest Income	24,319	21,444	18,345
Loss on sale of commercial loan	0	(1,238)	0
Securities gains, net	419	7,619	1,220
Total noninterest income	24,738	27,825	19,565
Noninterest expense
Salaries and wages	31,006	29,935	27,288
Employee benefits	7,327	7,710	5,875
Outsourced data processing costs	6,372	7,382	6,583
Telephone / data lines	1,253	1,178	1,179
Occupancy	7,178	8,146	7,627
Furniture and equipment	2,334	2,319	2,291
Marketing	2,339	3,095	2,917
Legal and professional fees	2,458	5,241	6,137
FDIC assessments	2,601	2,805	3,013
Amortization of intangibles	783	788	847
Asset disposition expense	740	1,459	2,281
Net loss on other real estate owned and repossessed assets	1,289	3,467	3,751
Other	9,472	9,023	7,974
Total noninterest expense	$ 75,152	$ 82,548	$ 77,763