Loans Receivable and Allowance for Loan Losses - Loan Portfolio Summarized by Aging Categories of Performing Loans and Nonaccrual Loans (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 665,862	$ 647,727
30-59 Days Past Due	1,857	3,264
60-89 Days Past Due	32	699
90+ (still accruing) Days Past Due	0	0
Total Past Due	1,889	3,963
Non-Accrual	12,623	19,347
Total Loans	680,374	671,037
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	314,907	325,397
Commercial Real Estate [Member] | Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	94,034	106,078
30-59 Days Past Due	207	742
60-89 Days Past Due	0	108
90+ (still accruing) Days Past Due	0	0
Total Past Due	207	850
Non-Accrual	3,160	4,362
Total Loans	97,401	111,290
Commercial Real Estate [Member] | Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	139,612	132,913
30-59 Days Past Due	115	191
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	115	191
Non-Accrual	2,419	2,849
Total Loans	142,146	135,953
Commercial Real Estate [Member] | Multi - Family [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	26,705	22,560
30-59 Days Past Due	0	0
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	0	0
Non-Accrual	96	322
Total Loans	26,801	22,882
Commercial Real Estate [Member] | Non-Owner Occupied Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	46,806	50,554
30-59 Days Past Due	113	225
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	113	225
Non-Accrual	1,640	4,493
Total Loans	48,559	55,272
Acquisition and Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	20,777	22,778
Acquisition and Development [Member] | 1-4 Family Residential Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	5,297	3,338
30-59 Days Past Due	0	0
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	0	0
Non-Accrual	0	0
Total Loans	5,297	3,338
Acquisition and Development [Member] | Commercial and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	14,604	17,289
30-59 Days Past Due	544	45
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	544	45
Non-Accrual	332	2,106
Total Loans	15,480	19,440
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	44,431	31,111
30-59 Days Past Due	0	334
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	0	334
Non-Accrual	694	2,001
Total Loans	45,125	33,446
Municipal [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	62,385	60,996
30-59 Days Past Due	0	0
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	0	0
Non-Accrual	0	0
Total Loans	62,385	60,996
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	231,058	222,236
Residential Mortgage [Member] | First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	121,750	119,845
30-59 Days Past Due	626	1,380
60-89 Days Past Due	25	577
90+ (still accruing) Days Past Due	0	0
Total Past Due	651	1,957
Non-Accrual	4,151	2,926
Total Loans	126,552	124,728
Residential Mortgage [Member] | Home Equity - Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	20,651	19,966
30-59 Days Past Due	110	56
60-89 Days Past Due	0	2
90+ (still accruing) Days Past Due	0	0
Total Past Due	110	58
Non-Accrual	72	107
Total Loans	20,833	20,131
Residential Mortgage [Member] | Home Equity - Lines of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	83,516	76,982
30-59 Days Past Due	115	214
60-89 Days Past Due	0	0
90+ (still accruing) Days Past Due	0	0
Total Past Due	115	214
Non-Accrual	42	181
Total Loans	83,673	77,377
Installment and Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	6,071	6,095
30-59 Days Past Due	27	77
60-89 Days Past Due	7	12
90+ (still accruing) Days Past Due	0	0
Total Past Due	34	89
Non-Accrual	17	0
Total Loans	$ 6,122	$ 6,184