Regulatory Requirements and Restrictions - Schedule of Bank's Actual Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Consolidated Entities
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	$ 49,097	$ 41,445
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	16.90%	15.02%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 23,242	$ 22,074
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	$ 38,817	$ 38,240
Tier 1 Capital (to Risk Weighted Assets), Actual Ratio	13.36%	13.86%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 11,621	$ 11,037
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	6.00%	4.00%
Tier 1 Capital (to Average Assets), Actual Amount	$ 38,817	$ 38,240
Tier 1 Capital (to Average Assets), Actual Ratio	9.52%	10.36%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Amount	$ 16,307	$ 14,770
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Ratio	4.00%	4.00%
Consolidated Entities | Common Stock
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	$ 38,817
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	13.36%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 11,621
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	4.50%
Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	$ 40,498	$ 36,446
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	14.08%	13.30%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 23,010	$ 21,927
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	$ 28,763	$ 27,409
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	$ 37,059	$ 33,241
Tier 1 Capital (to Risk Weighted Assets), Actual Ratio	12.88%	12.13%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 11,505	$ 10,964
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	6.00%	4.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 17,258	$ 16,445
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	$ 37,059	$ 33,241
Tier 1 Capital (to Average Assets), Actual Ratio	9.17%	9.07%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement Amount	$ 16,162	$ 14,664
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	$ 20,203	$ 18,329
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%
Subsidiaries | Common Stock
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk Based Capital (to Risk Weighted Assets), Actual Amount	$ 37,059
Total Risk Based Capital (to Risk Weighted Assets), Actual Ratio	12.88%
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Amount	$ 11,505
Total Risk Based Capital (to Risk Weighted Assets), Minimum Capital Requirement Ratio	4.50%
Total Risk Based Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 14,381
Total Risk Based Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%