Bank Premises and Equipment - Schedule of Bank Premises and Equipment (Detail) (USD $) In Thousands, unless otherwise specified											12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Land [Member]	Dec. 31, 2012 Land [Member]	Dec. 31, 2013 Bank Premises [Member]	Dec. 31, 2012 Bank Premises [Member]	Dec. 31, 2013 Furniture and Equipment [Member]	Dec. 31, 2012 Furniture and Equipment [Member]	Dec. 31, 2013 Leasehold Improvements [Member]	Dec. 31, 2012 Leasehold Improvements [Member]	Dec. 31, 2013 Minimum [Member] Bank Premises [Member]	Dec. 31, 2013 Minimum [Member] Furniture and Equipment [Member]	Dec. 31, 2013 Minimum [Member] Leasehold Improvements [Member]	Dec. 31, 2013 Maximum [Member] Bank Premises [Member]	Dec. 31, 2013 Maximum [Member] Furniture and Equipment [Member]	Dec. 31, 2013 Maximum [Member] Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Bank premises and equipment, gross	$ 64,688	$ 63,080	$ 3,478	$ 3,478	$ 19,235	$ 18,353	$ 31,965	$ 31,319	$ 10,010	$ 9,930
Accumulated depreciation and amortization	(41,288)	(39,181)
Total	$ 23,400	$ 23,899
Estimated Useful Life											30 years	3 years	30 years	39 years	10 years	39 years