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Commitments and Off-Balance Sheet Risk - Instruments Carried at Fair Value (Detail) (Standby letters of credit [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012
Standby letters of credit [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contract Amount	$ 19,670,000	$ 10,591,000
Carrying Value	$ 148,000	$ 218,000

X

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Period Type:	instant

X

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Period Type:	instant