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ACQUISITIONS Selected Pro Forma Results (Details 2) - Island Bancorp, Inc. [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Business Acquisition [Line Items] |  |  |  |
Net interest income after provision for loan losses | $ 67,073 | $ 58,119 | $ 191,485 | $ 171,221
Net income | $ 23,852 | $ 20,769 | $ 67,961 | $ 60,257

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- Definition 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. + 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=79982066&loc=d3e1392-128463 + Details
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