Securities - Unrealized Loss Positions (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	$ 8,608	$ 2,653
Less than 12 months, Unrealized Loss	56	11
12 months or more, Fair Value	5,183	12,538
12 months or more, Unrealized Loss	110	188
Fair Value, Total	13,791	15,191
Total Unrealized Loss	166	199
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	3,280	1,499
Less than 12 months, Unrealized Loss	18	4
12 months or more, Fair Value	1,745	3,532
12 months or more, Unrealized Loss	18	33
Fair Value, Total	5,025	5,031
Total Unrealized Loss	36	37
State and Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	5,328	412
Less than 12 months, Unrealized Loss	38	5
12 months or more, Fair Value	3,438	9,006
12 months or more, Unrealized Loss	92	155
Fair Value, Total	8,766	9,418
Total Unrealized Loss	$ 130	$ 160