Goodwill and Intangible Assets (Estimated Future Amortization Expense of Core Deposit Intangibles) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Future Amortization Expense For Core Deposit Intangibles
2012	$ 2,175
2013	3,964
2014	3,397
2015	2,645
2016	$ 2,184

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

+ References

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

+ References

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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