Acquisition of Bank of Granite Corporation (Pro Forma Information) (Details) (Granite Corp. [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010
Granite Corp. [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue	$ 7,868	$ 133,312	$ 180,090
Earnings (Loss)	$ 2,988	$ (123,343)	$ (135,605)

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration