Schedule of Comparison Capital with Minimum Requirements (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Company
Schedule Of Comparison Capital With Minimum Requirements [Line Items]
Total Capital (to Risk Weighted Assets) Actual Amount	$ 34,165,000	$ 32,186,000	$ 30,361,000
Total Capital (to Risk Weighted Assets) Actual Ratio	14.10%	14.40%	12.60%
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	19,425,729	17,943,415	19,307,000
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	8.00%	8.00%	8.00%
Tier I Capital (to Risk Weighted Assets) Actual Amount	31,124,000	26,365,000	27,337,000
Tier I Capital (to Risk Weighted Assets) Actual Ratio	12.80%	13.10%	11.30%
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	9,711,076	8,973,262	9,651,000
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%	4.00%
Tier I Capital (to Average Assets) Actual Amount	31,124,000	29,365,000	27,337,000
Tier I Capital (to Average Assets) Actual Ratio	8.30%	8.20%	7.60%
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Amount	15,072,155	14,324,390	14,313,000
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%	4.00%
Bank
Schedule Of Comparison Capital With Minimum Requirements [Line Items]
Total Capital (to Risk Weighted Assets) Actual Amount	33,807,000	31,884,000	29,974,000
Total Capital (to Risk Weighted Assets) Actual Ratio	14.00%	14.20%	12.40%
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	19,290,728	17,962,817	19,307,000
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	8.00%	8.00%	8.00%
Total Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	24,113,409	22,453,521	24,134,000
Total Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%	10.00%
Tier I Capital (to Risk Weighted Assets) Actual Amount	30,787,000	29,061,000	26,951,000
Tier I Capital (to Risk Weighted Assets) Actual Ratio	12.80%	12.90%	11.20%
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	9,643,540	8,983,308	9,651,000
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%	4.00%
Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	14,465,309	13,474,961	14,477,000
Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.00%	6.00%	6.00%
Tier I Capital (to Average Assets) Actual Amount	30,787,000	29,061,000	26,951,000
Tier I Capital (to Average Assets) Actual Ratio	8.10%	8.00%	7.70%
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Amount	15,297,888	14,530,500	13,928,000
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%	4.00%
Tier I Capital (to Average Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 19,122,360	$ 18,163,125	$ 17,410,000
Tier I Capital (to Average Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%	5.00%

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The amount of total capital as defined in the regulations.

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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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Tier 1 Risk Based Capital as defined in the regulations.

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

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