Regulatory Capital Requirements - Summary of Capital Requirements and Capital Position (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2013	Dec. 31, 2013 Parent Company [Member]	Dec. 31, 2012 Parent Company [Member]	Dec. 31, 2013 Consolidated [Member]	Dec. 31, 2012 Consolidated [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (To Risk Weighted Assets), Actual Amount		$ 295,940	$ 281,681	$ 303,059	$ 286,436
Tier 1 Capital (To Risk Weight Assets), Actual Amount		274,239	261,421	281,310	266,150
Tier 1 Capital (To Average Assets), Actual Amount		274,239	261,421	281,310	266,150
Total Capital (To Risk Weighted assets), Actual Ratio		17.10%	17.40%	17.50%	17.70%
Tier 1 Capital (To Risk Weighted Assets), Actual Ratio		15.80%	16.20%	16.20%	16.50%
Tier 1 Capital (To Average Assets), Actual Ratio		9.30%	9.20%	9.50%	9.30%
Total Capital (To Risk Weighted Assets), Minimum for Capital Adequacy, Amount		138,533	129,152	138,843	129,318
Tier 1 Capital (To Risk Weighted Assets), Minimum for Capital Adequacy, Amount		69,267	64,576	69,422	64,659
Tier 1 Capital (To Average assets), Minimum for Capital Adequacy, Amount		118,062	114,100	118,257	114,259
Total Capital (To Risk Weighted Assets), Minimum for Capital Adequacy, Ratio		8.00%	8.00%	8.00%	8.00%
Tier 1 Capital (To Risk Weighted Assets), Minimum for Capital Adequacy, Ratio		4.00%	4.00%	4.00%	4.00%
Tier 1 Capital (To Average Assets), Minimum for Capital Adequacy, Ratio		4.00%	4.00%	4.00%	4.00%
Total Capital (To Risk Weighted Assets) ,Minimum to be Well Capitalized Under Prompt Corrective Action, Amount		173,167	161,439
Tier 1 Capital (To Risk Weighted Assets) , Minimum to be Well Capitalized Under Prompt Corrective Action, Amount		103,900	96,864
Tier 1 Capital (To Average Assets), Minimum to be Well Capitalized Under Prompt Corrective Action, Amount		$ 147,578	$ 142,625
Total Capital (To Risk Weighted Assets), Minimum to be Well Capitalized Under Prompt Corrective Action, Ratio	10.00%	10.00%	10.00%
Tier 1 Capital (To Risk Weighted Assets), Minimum to be Well Capitalized Under Prompt Corrective Action, Ratio	6.00%	6.00%	6.00%
Tier 1 Capital (To Average Assets), Minimum to be Well Capitalized Under Prompt Corrective Action, Ratio	5.00%	5.00%	5.00%