MERGERS AND ACQUISITIONS - Pro Forma Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Total interest and non-interest income	$ 212,531	$ 208,608
East Carolina Bancorp, Inc
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net interest income	157,805	153,437
Net income	34,370	23,009
Net income available to common shareholders	$ 31,934	$ 20,867
Basic income per common share (in dollars per share)	$ 1.02	$ 0.73
Diluted income per common share (in dollars per share)	$ 1.02	$ 0.73
Weighted average basic common shares outstanding (in shares)	31,295,562	28,568,000
Weighted average diluted common shares outstanding (in shares)	31,375,585	28,640,684

Business Acquisition, Pro Forma Net Interest Income

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Business Acquisition, Pro Forma, Weighted Average Number of Shares Outstanding, Basic

+ References

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Business Acquisition, Pro Forma, Weighted Average Number of Shares Outstanding, Diluted

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- Definition

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock 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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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, 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 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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