Carrying Amount And Estimated Fair Value Of Financial Instruments (Detail) (Fair Value Measurements Nonrecurring [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Impaired loans, net of related allowance	$ 33,883	$ 33,072
Other real estate owned	9,685	12,275
Total assets at fair value	43,568	45,347
Fair Value Inputs Level 3 [Member]
Impaired loans, net of related allowance	33,883	33,072
Other real estate owned	9,685	12,275
Total assets at fair value	$ 43,568	$ 45,347

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of assets categorized as other which are not in and of themselves material enough to require separate disclosure.

No definition available.

Name:	us-gaap_OtherAssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant