Fair Value Disclosures - Summary of Assets Measured at Fair Value on Nonrecurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Summary of assets measured at fair value on a nonrecurring basis
Foreclosed real estate	$ 1,128	$ 987
Fair Value, Measurements, Nonrecurring [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	4,795	4,951
Foreclosed real estate	718	558
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate [Member] | Owner-Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,389	1,031
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate [Member] | Non-Owner Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	350	694
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate [Member] | Multi - Family [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	96	322
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate [Member] | Non-Owner Occupied Residential [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,087	1,662
Fair Value, Measurements, Nonrecurring [Member] | Acquisition And Development [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	141	51
Fair Value, Measurements, Nonrecurring [Member] | Commercial and Industrial [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	29	592
Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,689	599
Fair Value, Measurements, Nonrecurring [Member] | Installment and Other Loans [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	14
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Foreclosed real estate	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Commercial Real Estate [Member] | Owner-Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Commercial Real Estate [Member] | Multi - Family [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied Residential [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Acquisition And Development [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Commercial and Industrial [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Residential Mortgage [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Installment and Other Loans [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Foreclosed real estate	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Commercial Real Estate [Member] | Owner-Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Commercial Real Estate [Member] | Multi - Family [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied Residential [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Acquisition And Development [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Commercial and Industrial [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Residential Mortgage [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Installment and Other Loans [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	0
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	4,795	4,951
Foreclosed real estate	718	558
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Commercial Real Estate [Member] | Owner-Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,389	1,031
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	350	694
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Commercial Real Estate [Member] | Multi - Family [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	96	322
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Commercial Real Estate [Member] | Non-Owner Occupied Residential [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,087	1,662
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Acquisition And Development [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	141	51
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Commercial and Industrial [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	29	592
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Residential Mortgage [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	1,689	599
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Installment and Other Loans [Member]
Summary of assets measured at fair value on a nonrecurring basis
Impaired loans, net	$ 14