Securities - Unrealized Loss Positions (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	$ 2,653	$ 19,063
Less than 12 months, Unrealized Loss	11	1,186
12 months or more, Fair Value	12,538	3,768
12 months or more, Unrealized Loss	188	142
Fair Value, Total	15,191	22,831
Total Unrealized Loss	199	1,328
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	742
Less than 12 months, Unrealized Loss	2
Fair Value, Total	742
Total Unrealized Loss	2
US Government Agencies
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	1,499	4,808
Less than 12 months, Unrealized Loss	4	66
12 months or more, Fair Value	3,532	1,462
12 months or more, Unrealized Loss	33	20
Fair Value, Total	5,031	6,270
Total Unrealized Loss	37	86
State and Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	412	14,255
Less than 12 months, Unrealized Loss	5	1,120
12 months or more, Fair Value	9,006	2,306
12 months or more, Unrealized Loss	155	122
Fair Value, Total	9,418	16,561
Total Unrealized Loss	$ 160	$ 1,242