Allowance for Loan Losses - Loan Receivables Evaluated for Impairment Individually and Collectively by Segment (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	$ 13,338	$ 10,826
Collectively evaluated for impairment	336,061	336,396
Total Gross Loans	349,399	347,222
Mortgage Loans on Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	13,063	10,542
Collectively evaluated for impairment	298,309	296,561
Total Gross Loans	311,372	307,103
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	275	284
Collectively evaluated for impairment	32,715	34,820
Total Gross Loans	32,990	35,104
Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collectively evaluated for impairment	5,037	5,015
Total Gross Loans	$ 5,037	$ 5,015