Acquisition Activity - Supplemental Pro Forma Information (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2014 USD ($) $ / shares
Business Acquisition, Pro Forma Information [Abstract]
Interest and non-interest income \| $	$ 586,979
Net income \| $	$ 88,615
Earnings per share - basic (in usd per share)	$ 2.28
Earnings per share - diluted (in usd per share)	$ 2.28

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.

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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- Definition

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.

+ References

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- References

No definition available.

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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

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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