Regulatory Capital Matters - Actual Capital Levels and Minimum Required Levels for Bank (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Banking and Thrift [Abstract]
Total capital (to risk-weighted assets), Actual Amount	$ 9,883us-gaap_Capital	$ 8,510us-gaap_Capital
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	9,234
Tier 1 (core) capital (to risk-weighted assets), Actual Amount	9,234us-gaap_TierOneRiskBasedCapital	7,818us-gaap_TierOneRiskBasedCapital
Tier 1 (core) capital (to adjusted total assets), Actual Amount	9,234us-gaap_TierOneLeverageCapital	7,818us-gaap_TierOneLeverageCapital
Total capital (to risk-weighted assets), Actual Ratio	19.20%us-gaap_CapitalToRiskWeightedAssets	15.50%us-gaap_CapitalToRiskWeightedAssets
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	18.00%
Tier 1 (core) capital (to risk-weighted assets), Actual Ratio	18.00%	14.30%
Tier 1 (core) capital (to adjusted total assets), Actual Ratio	10.50%	8.70%
Total capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Amount	4,112	4,387
Common equity Tier 1 capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Amount	2,313
Tier 1 (core) capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Amount	3,084	2,193
Tier 1 (core) capital (to adjusted total assets), Minimum Required for Capital Adequacy Purposes Amount	2,531	3,580
Total capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Ratio	8.00%	8.00%
Common equity Tier 1 capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Ratio	4.50%
Tier 1 (core) capital (to risk-weighted assets), Minimum Required for Capital Adequacy Purposes Ratio	6.00%	4.00%
Tier 1 (core) capital (to adjusted total assets), Minimum Required for Capital Adequacy Purposes Ratio	4.00%	4.00%
Total capital (to risk-weighted assets), Minimum Required By the Current Order Amount	6,766	7,129
Tier 1 (core) capital (to adjusted total assets), Minimum Required By the Current Order Amount	$ 7,809	$ 8,054
Total capital (to risk-weighted assets), Minimum Required By the Current Order Ratio	13.00%	13.00%
Tier 1 (core) capital (to adjusted total assets), Minimum Required By the Current Order Ratio	9.00%	9.00%

Common Equity Tier One Risk Based Capital

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Common Equity Tier One Risk Based Capital Required For Capital Adequacy

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Common Equity Tier One Risk Based Capital Required For Capital Adequacy 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 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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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in 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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Tier 1 capital divided by risk weighted assets as defined by regulations.

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