Regulatory Requirements and Restrictions - Schedule of Bank's Actual Capital Amounts and Ratios (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Consolidated Entities
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	$ 41,445	$ 39,322
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	15.02%	16.38%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	22,074	19,211
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	8.00%	8.00%
Tier 1 Capital (to Risk Weighted Assets), Actual Amount	38,240	36,397
Tier 1 Capital (to Risk Weighted Assets), Actual Ratio	13.86%	15.16%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	11,037	9,605
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	4.00%	4.00%
Tier 1 Capital (to Average Assets), Actual Amount	38,240	36,397
Tier 1 Capital (to Average Assets), Actual Ratio	10.35%	10.93%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Amount	14,770	13,319
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Ratio	4.00%	4.00%
Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	36,446	33,419
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	13.30%	14.01%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	21,927	19,089
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	8.00%	8.00%
Total Risk Based Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	27,409	23,861
Total Risk Based Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%
Tier 1 Capital (to Risk Weighted Assets), Actual Amount	33,241	30,494
Tier 1 Capital (to Risk Weighted Assets), Actual Ratio	12.13%	12.78%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	10,964	9,545
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	4.00%	4.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	16,445	14,317
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.00%	6.00%
Tier 1 Capital (to Average Assets), Actual Amount	33,241	30,494
Tier 1 Capital (to Average Assets), Actual Ratio	9.07%	9.20%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Amount	14,664	13,259
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Ratio	4.00%	4.00%
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 18,329	$ 16,573
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%