Acquisitions Pro Forma Financial Information of Combined Entities (Details) - Highland County Bankshares Inc and First Century Bankshares Inc [Member] - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Total revenues, net of interest expense	$ 64,313	$ 61,457
Net income	$ 11,176	$ 15,017
Diluted earnings per share (in USD per share)	$ 0.95	$ 1.23

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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=65885119&loc=d3e1392-128463

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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.

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

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