Mergers and Acquisitions (Details 2) - Metropolitan Bancgroup, Inc. - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Net interest income	$ 356,787	$ 340,796
Net income	$ 89,554	$ 102,881
Earnings per share, basic (usd per share)	$ 1.82	$ 2.21
Earnings per share, diluted (usd per share)	$ 1.81	$ 2.19

Business Acquisition, Pro Forma Net Interest Income

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- Definition

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.

+ References

No definition available.

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- Definition

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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