Related-Party Transactions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Related Party Transaction [Line Items]
Related party loans	$ 47.8	$ 66.6
Related party loans funded	36.4
Related Party loans repaid	55.2
Related party deposit	17.9	16.1
Building [Member]
Related Party Transaction [Line Items]
Rent incurred for lease	$ 0.2	$ 0.2	$ 0.2
Lease terms	The lease also includes options for multiple five-year term extensions beyond the original lease expiration of October 2004
Lease expiration date	Oct. 31, 2004
Building [Member] | Director [Member]
Related Party Transaction [Line Items]
Number of building leased	1