Loans - Summary of Loans by Credit Quality Indicator (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 432,985	$ 422,413
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	128,924	123,143
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	153,008	148,775
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	127,099	125,775
Construction & Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	13,571	15,452
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	10,383	9,268
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	276,615	265,055
Pass [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	118,269	112,229
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	146,445	141,621
Pass [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	223	190
Pass [Member] | Construction & Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	11,678	11,015
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,164	6,786
Special Mention [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,776	3,100
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,664	2,742
Special Mention [Member] | Construction & Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	724	944
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	10,168	10,407
Substandard [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,990	7,044
Substandard [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,976	3,150
Substandard [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	202	213
Not Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	140,038	140,165
Not Rated [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	889	770
Not Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	923	1,262
Not Rated [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	126,674	125,372
Not Rated [Member] | Construction & Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,169	3,493
Not Rated [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 10,383	$ 9,268