Loans and Allowance for Loan Losses - Allowance for Loan Losses Outstanding by Impairment Methodology (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	$ 5,469	$ 7,005
Collectively evaluated for impairment	33,565	31,720
Non-residential real estate owner occupied [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	231	238
Collectively evaluated for impairment	4,596	4,866
Non-residential real estate other [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	2,449	2,521
Collectively evaluated for impairment	8,577	7,344
Residential real estate primary mortgage [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	243	278
Collectively evaluated for impairment	2,582	2,503
Residential real estate all other [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	994	2,025
Collectively evaluated for impairment	5,714	5,009
Non-consumer non-real estate [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	966	1,403
Collectively evaluated for impairment	8,011	7,982
Consumer non-real estate [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	334	287
Collectively evaluated for impairment	2,222	2,164
Other loans [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment	252	253
Collectively evaluated for impairment	1,739	1,632
Acquired loans [Member]
Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment [Line Items]
Individually evaluated for impairment
Collectively evaluated for impairment	$ 124	$ 220