Mergers and Acquisitions - Pro Forma Combined Condensed Consolidated Financial Information (Details) - Metropolitan Bancgroup, Inc. - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Net interest income - pro forma (unaudited)	$ 263,525	$ 252,366
Net income - pro forma (unaudited)	$ 72,915	$ 75,744
Earnings per share - pro forma (unaudited):
Basic (usd per share)	$ 1.50	$ 1.68
Diluted (usd per share)	$ 1.50	$ 1.67

Business Acquisition, Pro Forma Net Interest Income

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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=79982066&loc=d3e1392-128463

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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.

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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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