Estimated Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Financial assets
Cash and cash equivalents	$ 25,291	$ 39,164	$ 31,017	$ 23,474
Held-to-maturity securities	235	450
Loans, net of allowance	309,225	313,354
Federal Home Loan Bank stock	4,210	4,210
Accrued interest receivable	792	829
Financial liabilities
Deposits	323,442	322,681
Short term borrowings	9,028	5,098
Federal Home Loan Bank advances	26,635	26,719
Subordinated debentures	4,124	4,124
Interest payable	127	135
Fair Value, Inputs, Level 1
Financial assets
Cash and cash equivalents	25,291	0
Held-to-maturity securities	0	0
Loans, net of allowance	0	0
Federal Home Loan Bank stock	0	0
Accrued interest receivable	0	0
Financial liabilities
Deposits	0	0
Short term borrowings	0	0
Federal Home Loan Bank advances	0	0
Subordinated debentures	0	0
Interest payable	0	0
Fair Value, Inputs, Level 2
Financial assets
Cash and cash equivalents	0	0
Held-to-maturity securities	236	451
Loans, net of allowance	0	0
Federal Home Loan Bank stock	4,210	4,210
Accrued interest receivable	792	829
Financial liabilities
Deposits	308,801	309,186
Short term borrowings	9,028	5,098
Federal Home Loan Bank advances	27,891	26,703
Subordinated debentures	3,962	3,962
Interest payable	127	135
Fair Value, Inputs, Level 3
Financial assets
Cash and cash equivalents	0	0
Held-to-maturity securities	0	0
Loans, net of allowance	307,513	312,014
Federal Home Loan Bank stock	0	0
Accrued interest receivable	0	0
Financial liabilities
Deposits	0	0
Short term borrowings	0	0
Federal Home Loan Bank advances	0	0
Subordinated debentures	0	0
Interest payable	$ 0	$ 0