Business Combinations - Proforma Financial Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Business Combinations [Abstract]
Total revenue (net interest income plus other income)	$ 263,070	$ 253,668
Net income	61,572	39,979
Net income available to common shareholders	$ 61,572	$ 37,599
Earnings per share:
Basic	$ 1.63	$ 0.98
Diluted	$ 1.61	$ 0.97

Business Acquisition, Pro Forma Net Income Loss, Attributable to Parent

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- Definition

Business Acquisition, Pro Forma Revenue, Net Interest Income Plus Other Income

+ References

No definition available.

+ Details

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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=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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- 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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