Capital Requirements - Comparison of Capital of Bank with Minimum Regulatory Guidelines (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Regulatory Capital Requirements [Abstract]
Actual Amount Total Capital (to Risk Weighted Assets)	$ 60,232	$ 71,941
Actual Ratio Total Capital (to Risk Weighted Assets)	14.59%	19.14%
Minimum Capital Requirement Amount Total Capital (to Risk Weighted Assets)	$ 33,032	$ 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)	$ 41,290	$ 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)	$ 55,066	$ 67,217
Actual Ratio Tier 1 Capital (to Risk Weighted Assets)	13.34%	17.88%
Minimum Capital Requirement Amount Tier 1 Capital (to Risk Weighted Assets)	$ 24,774	$ 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)	$ 33,032	$ 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)	$ 55,066
Actual Ratio Common Equity Tier 1 Capital (to Risk Weighted Assets)	13.34%
Minimum Capital Requirement Amount Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 18,580
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)	$ 26,838
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)	$ 55,066	$ 67,217
Actual Ratio Tier 1 Capital (to Average Assets)	7.99%	12.90%
Minimum Capital Requirement Amount Tier 1 Capital (to Average Assets)	$ 27,581	$ 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)	$ 34,476	$ 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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