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Segments - Total Assets by Reportable Operating Segment (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	$ 6,133,728	$ 4,964,686
Operating Segments [Member] | Community Banking [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	6,121,771	4,954,728
Operating Segments [Member] | Insurance [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	8,232	7,468
Operating Segments [Member] | Wealth Management [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	$ 3,725	$ 2,490

X

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 210



-SubTopic 10



-Section S99



-Paragraph 1



-Subparagraph (SX 210.5-02.18)



-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 210



-SubTopic 10



-Section S99



-Paragraph 1



-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 3: http://www.xbrl.org/2003/role/presentationRef



-Publisher SEC



-Name Regulation S-X (SX)



-Number 210



-Section 03



-Paragraph 12



-Article 7

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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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