Loans and Allowance - Subsequent Default (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 loan	Dec. 31, 2012 loan
Financing Receivable, Impaired [Line Items]
Number of Loans	5	7
Recorded Balance	$ 1,207	$ 620
Commercial and industrial loans
Financing Receivable, Impaired [Line Items]
Number of Loans	3	1
Recorded Balance	173	23
Commercial and farmland
Financing Receivable, Impaired [Line Items]
Number of Loans	2	2
Recorded Balance	1,034	212
Residential
Financing Receivable, Impaired [Line Items]
Number of Loans		4
Recorded Balance		$ 385