Disclosures About Fair Value of Financial Instruments - Estimates of Fair Values of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	$ 23,852	$ 31,875
Investment securities	205,679	199,955
Loans	89,104	91,537
Accrued interest receivable	1,298	1,168
Financial liabilities:
Deposits	279,554	285,877
Federal funds purchased and repurchase agreements	20,739	20,215
Federal Home Loan Bank borrowings	3,492	3,516
Accrued interest payable	124	134
Level I [Member]
Financial assets:
Cash and cash equivalents	23,852	31,875
Investment securities	196	195
Accrued interest receivable	1,298	1,168
Financial liabilities:
Deposits	193,847	195,135
Federal funds purchased and repurchase agreements	20,739	20,215
Accrued interest payable	124	134
Level II [Member]
Financial assets:
Investment securities	205,483	199,760
Financial liabilities:
Deposits	65,407	67,308
Federal Home Loan Bank borrowings	3,885	3,917
Level III [Member]
Financial assets:
Loans	90,096	91,413
Fair Value [Member]
Financial assets:
Cash and cash equivalents	23,852	31,875
Investment securities	205,679	199,955
Loans	90,096	91,413
Accrued interest receivable	1,298	1,168
Financial liabilities:
Deposits	259,254	262,443
Federal funds purchased and repurchase agreements	20,739	20,215
Federal Home Loan Bank borrowings	3,885	3,917
Accrued interest payable	$ 124	$ 134