Loans Receivable and Allowance for Loan Losses - Summary of Allowance for Loan Loss Allocation (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	$ 20,541	$ 25,335
Loans, Collectively evaluated for impairment	652,741	645,702
Total Loans	673,282	671,037
Allowance for loan losses, Individually evaluated for impairment	433	613
Allowance for loan losses, Collectively evaluated for impairment	20,064	20,352
Allowance for loan losses, Total	20,497	20,965	21,917	23,166
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	13,443	16,494
Loans, Collectively evaluated for impairment	312,584	308,903
Total Loans	326,027	325,397
Allowance for loan losses, Individually evaluated for impairment	433	552
Allowance for loan losses, Collectively evaluated for impairment	13,286	12,663
Allowance for loan losses, Total	13,719	13,215	12,165	13,719
Acquisition and Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	1,399	3,177
Loans, Collectively evaluated for impairment	19,389	19,601
Total Loans	20,788	22,778
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	474	670
Allowance for loan losses, Total	474	670	2,614	3,502
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	2,176	2,001
Loans, Collectively evaluated for impairment	33,970	31,445
Total Loans	36,146	33,446
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	919	864
Allowance for loan losses, Total	919	864	1,353	1,635
Municipal [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	60,927	60,996
Total Loans	60,927	60,996
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	244	244
Allowance for loan losses, Total	244	244	285	223
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	17,018	21,672
Loans, Collectively evaluated for impairment	426,870	420,945
Total Loans	443,888	442,617
Allowance for loan losses, Individually evaluated for impairment	433	552
Allowance for loan losses, Collectively evaluated for impairment	14,923	14,441
Allowance for loan losses, Total	15,356	14,993	16,417	19,079
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	3,523	3,663
Loans, Collectively evaluated for impairment	220,209	218,573
Total Loans	223,732	222,236
Allowance for loan losses, Individually evaluated for impairment	0	61
Allowance for loan losses, Collectively evaluated for impairment	3,112	3,719
Allowance for loan losses, Total	3,112	3,780	3,388	2,275
Installment and Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	5,662	6,184
Total Loans	5,662	6,184
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	126	124
Allowance for loan losses, Total	126	124	112	85
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	3,523	3,663
Loans, Collectively evaluated for impairment	225,871	224,757
Total Loans	229,394	228,420
Allowance for loan losses, Individually evaluated for impairment	0	61
Allowance for loan losses, Collectively evaluated for impairment	3,238	3,843
Allowance for loan losses, Total	3,238	3,904	3,500	2,360
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	0	0
Total Loans	0	0
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	1,903	2,068
Allowance for loan losses, Total	$ 1,903	$ 2,068	$ 2,000	$ 1,727

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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