Recorded Investment in Loans Related to Balance in Allowance for Possible Loan Losses by Portfolio Segment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	$ 14,500	$ 11,399
Loans collectively evaluated for general impairment	363,942	378,067
Total Gross Loans	378,442	389,466
Real Estate Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	14,073	10,659
Loans collectively evaluated for general impairment	281,396	302,107
Total Gross Loans	295,469	312,766
Business Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	179	305
Loans collectively evaluated for general impairment	39,835	37,855
Total Gross Loans	40,014	38,160
Consumer Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	248	435
Loans collectively evaluated for general impairment	42,711	38,105
Total Gross Loans	$ 42,959	$ 38,540

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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=7512638&loc=SL6953423-111524

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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