Fair Value Disclosures - Other Real Estate Owned (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Fair Value Disclosures [Abstract]
Carrying value of other real estate owned prior to re-measurement	$ 1,827	$ 417
Write-downs included in gain (loss) on sale of other real estate owned	(304)	(101)
Fair value	$ 1,523	$ 316

Write Downs Included In Gain Loss On Sale Of Other Real Estate Owned.

No definition available.

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Period Type:	duration