Allowance for Loan Losses - Summary of Properties Included in Other Real Estate Owned (OREO) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014 Property	Dec. 31, 2013 Property
Real Estate Properties [Line Items]
No. of Properties	27	30
Carrying Value	$ 2,839	$ 3,897	[1]
Residential
Real Estate Properties [Line Items]
No. of Properties	10	11
Carrying Value	1,593	2,442
Land lots
Real Estate Properties [Line Items]
No. of Properties	13	14
Carrying Value	601	684
Convenience Store
Real Estate Properties [Line Items]
No. of Properties	2	2
Carrying Value	234	239
Restaurant
Real Estate Properties [Line Items]
No. of Properties	1	1
Carrying Value	107	107
Commercial properties
Real Estate Properties [Line Items]
No. of Properties	1	2
Carrying Value	$ 304	$ 425

[1] Derived from the audited consolidated financial statements.