Allowance for Loan Losses - Loan Receivables Evaluated for Impairment Individually and Collectively by Segment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	$ 6,858	$ 6,656
Collectively evaluated for impairment	291,196	243,675
Total Gross Loans	298,054	250,331
Mortgage Loans on Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	6,842	6,306
Collectively evaluated for impairment	251,861	214,101
Total Gross Loans	258,703	220,407
Commercial and Industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment		311
Collectively evaluated for impairment	34,002	23,627
Total Gross Loans	34,002	23,938
Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	16	39
Collectively evaluated for impairment	5,333	5,947
Total Gross Loans	$ 5,349	$ 5,986

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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=35738203&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=28367877&loc=d3e4428-111522

+ Details

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