Capital Requirements - Comparison of Capital of Bank with Minimum Regulatory Guidelines (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Regulatory Capital Requirements [Abstract]
Actual Amount Total Capital (to Risk Weighted Assets)	$ 72,764us-gaap_Capital	$ 71,941us-gaap_Capital
Actual Ratio Total Capital (to Risk Weighted Assets)	18.86%us-gaap_CapitalToRiskWeightedAssets	19.14%us-gaap_CapitalToRiskWeightedAssets
Minimum Capital Requirement Amount Total Capital (to Risk Weighted Assets)	30,859	30,077
Minimum Capital Requirement Ratio Total Capital (to Risk Weighted Assets)	8.00%	8.00%
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Total Capital (to Risk Weighted Assets)	38,573	37,596
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio Total Capital (to Risk Weighted Assets)	10.00%	10.00%
Actual Amount Tier 1 Capital (to Risk Weighted Assets)	67,918us-gaap_TierOneRiskBasedCapital	67,217us-gaap_TierOneRiskBasedCapital
Actual Ratio Tier 1 Capital (to Risk Weighted Assets)	17.61%	17.88%
Minimum Capital Requirement Amount Tier 1 Capital (to Risk Weighted Assets)	23,144	15,038
Minimum Capital Requirement Ratio Tier 1 Capital (to Risk Weighted Assets)	6.00%	4.00%
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Tier 1 Capital (to Risk Weighted Assets)	30,859	22,557
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio Tier 1 Capital (to Risk Weighted Assets)	8.00%	6.00%
Actual Amount Common Equity Tier 1 Capital (to Risk Weighted Assets)	67,918
Actual Ratio Common Equity Tier 1 Capital (to Risk Weighted Assets)	17.61%
Minimum Capital Requirement Amount Common Equity Tier 1 Capital (to Risk Weighted Assets)	17,358
Minimum Capital Requirement Ratio Common Equity Tier 1 Capital (to Risk Weighted Assets)	4.50%
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Common Equity Tier 1 Capital (to Risk Weighted Assets)	25,073
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio Common Equity Tier 1 Capital (to Risk Weighted Assets)	6.50%
Actual Amount Tier 1 Capital (to Average Assets)	67,918us-gaap_TierOneLeverageCapital	67,217us-gaap_TierOneLeverageCapital
Actual Ratio Tier 1 Capital (to Average Assets)	13.17%	12.90%
Minimum Capital Requirement Amount Tier 1 Capital (to Average Assets)	20,628	20,841
Minimum Capital Requirement Ratio Tier 1 Capital (to Average Assets)	4.00%	4.00%
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Tier 1 Capital (to Average Assets)	$ 25,785	$ 26,051
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio Tier 1 Capital (to Average Assets)	5.00%	5.00%

Common Equity Tier One Risk Based Capital

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Common Equity Tier One Risk Based Capital Required To Be Well Capitalized

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Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets

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Common Equity Tier One Risk Based Capital To Risk Weighted Assets

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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