Other Real Estate Owned (OREO) - Summary of Changes in the Allowance for OREO Losses (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Real Estate [Abstract]
Balance at beginning of year	$ 2,174	$ 2,792	$ 2,792
Provision for losses	660	595	1,190
Transfer in	63
Charge-offs, net	(1,332)	(1,539)	(1,808)
Balance at end of period	$ 1,565	$ 1,847	$ 2,174

Real estate owned valuation allowance additions.

No definition available.

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- Details

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- Definition

For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

+ 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 210.9-03.10(4))

-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 10

-Subparagraph 4

-Article 9

+ Details

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- Definition

Amount of the valuation allowance for real estate owned that was applied in the period against the carrying amount of real estate owned that was sold, written down or written off.

+ References

+ Details

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- Definition

Amount of the increase in the real estate owned valuation allowance that is charged against earnings in the period.

+ References

+ Details

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