Loans - Modified Commercial Loan (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013 Loan	Dec. 31, 2012 Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	1
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	1
Pre-Modification Outstanding Recorded Investment	$ 808	$ 808
Post-Modification Outstanding Recorded Investment	$ 346	$ 351

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524

+ Details

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- Definition

Amount of investment in financing receivables (after modification) modified by troubled debt restructurings.

+ References

+ Details

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- Definition

Amount of investment in financing receivables (before modification) modified by troubled debt restructurings.

+ References

+ Details

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