Modifications of Loans Performing (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due 30-89	$ 3,697	$ 7,163
Past Due 90 days and still accuring	92	669
Non- Accrual	6,513	6,056	$ 64
Total	731,037	704,531
Loans
Financing Receivable Recorded Investment Past Due [Line Items]
Current Loans	2,608	2,880
Past Due 30-89	0	622
Past Due 90 days and still accuring	0	0
Non- Accrual	3,982	3,281
Total	6,590	6,783
Allowance for loan losses, Current Loans	107	120
Allowance for loan losses, Past Due 30-89	0	11
Allowance for loan losses, Past Due 90 days and still accruing	0	103
Allowance for loan losses, Non-Accural	190	0
Allowance for loan losses, Total	297	234
Loans | Commercial installment
Financing Receivable Recorded Investment Past Due [Line Items]
Current Loans	221	233
Past Due 30-89	0	0
Past Due 90 days and still accuring	0	0
Non- Accrual	55	0
Total	276	233
Loans | Commercial real estate
Financing Receivable Recorded Investment Past Due [Line Items]
Current Loans	1,674	1,685
Past Due 30-89	0	0
Past Due 90 days and still accuring	0	0
Non- Accrual	2,642	2,729
Total	4,316	4,414
Loans | Consumer real estate
Financing Receivable Recorded Investment Past Due [Line Items]
Current Loans	704	952
Past Due 30-89	0	622
Past Due 90 days and still accuring	0	0
Non- Accrual	1,253	449
Total	1,957	2,023
Loans | Commercial installment
Financing Receivable Recorded Investment Past Due [Line Items]
Current Loans	9	10
Past Due 30-89	0	0
Past Due 90 days and still accuring	0	0
Non- Accrual	32	103
Total	$ 41	$ 113