Condensed Financial Information of Parent Company - Condensed Income Statements (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Non-interest income	$ 3,681us-gaap_NoninterestIncome	$ 4,726us-gaap_NoninterestIncome
Non-interest expense	12,618us-gaap_NoninterestExpense	12,943us-gaap_NoninterestExpense
Income tax expense (benefit)	557us-gaap_IncomeTaxExpenseBenefit	399us-gaap_IncomeTaxExpenseBenefit
Net income	1,830us-gaap_NetIncomeLoss	1,222us-gaap_NetIncomeLoss
Parent Company
Condensed Financial Statements, Captions [Line Items]
Non-interest income	641	600
Non-interest expense	622	829
Income (loss) before income taxes and equity in undistributed earnings of subsidiaries	19	(229)
Income tax expense (benefit)	5	(27)
Income (loss) before equity in undistributed earnings of subsidiaries	14	(202)
Equity in undistributed earnings of subsidiaries	1,816	1,424
Net income	$ 1,830	$ 1,222

Equity method of investment income after tax.

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Income (loss) before equity in undistributed earnings of subsidiaries.

+ References

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Income (loss) before income taxes and equity in undistributed earnings of subsidiaries.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Glossary Income Tax Expense (or Benefit)

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Total aggregate amount of all noninterest expense.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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