Note 2 - Mergers and Acquisitions (Details) - Unaudited Proforma Information (Virginia Heritage Bank [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Virginia Heritage Bank [Member]
Note 2 - Mergers and Acquisitions (Details) - Unaudited Proforma Information [Line Items]
Net interest income	$ 206,721	$ 174,509
Net income	$ 58,756	$ 55,973
Earnings per share:
Basic	$ 1.89	$ 1.86
Diluted	$ 1.82	$ 1.81

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The pro forma basic 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=25497992&loc=d3e1392-128463

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+ References

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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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