Loans - Summary of Loan Classes and an Aging of Past Due Loans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	$ 3,523	$ 3,005
60-89 Days Past Due	1,300	4,809
> 90 Days Past Due	3,273	3,571
Total Past Due	8,096	11,385
Current	370,314	345,708
Total loans	378,410	357,093	383,594
Non- Accrual Loans	8,000	11,678
90 Days or More Past Due and Accruing		49
Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	2,441	161
60-89 Days Past Due	71	2,852
> 90 Days Past Due		3,339
Total Past Due	2,512	6,352
Current	26,963	27,708
Total loans	29,475	34,060	43,524
Non- Accrual Loans	1,787	5,811
Secured by 1-4 Family Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	504	1,561
60-89 Days Past Due	323	316
> 90 Days Past Due	754	136
Total Past Due	1,581	2,013
Current	162,146	139,948
Total loans	163,727	141,961	134,964
Non- Accrual Loans	1,342	953
90 Days or More Past Due and Accruing		27
Other Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	554	1,077
60-89 Days Past Due	800	1,636
> 90 Days Past Due	2,519	74
Total Past Due	3,873	2,787
Current	147,929	143,181
Total loans	151,802	145,968
Non- Accrual Loans	4,756	4,756
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	10	165
60-89 Days Past Due	106
> 90 Days Past Due		22
Total Past Due	116	187
Current	21,050	22,616
Total loans	21,166	22,803	23,071
Non- Accrual Loans	115	144
90 Days or More Past Due and Accruing		22
Consumer and Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	14	41
60-89 Days Past Due		5
Total Past Due	14	46
Current	12,226	12,255
Total loans	12,240	12,301	7,815
Non- Accrual Loans		$ 14

Financing receivables that are less than 60 days past due but more than 29 days past due.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Financing receivables that are current.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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