Goodwill and Other Intangible Assets (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Core deposit intangibles
Estimated future amortization expense
Year ending December 31, 2012	$ 3,200
Year ending December 31, 2013	3,100
Year ending December 31, 2014	2,900
Year ending December 31, 2015	1,400
Year ending December 31, 2016	300
Other Intangibles
Estimated future amortization expense
Year ending December 31, 2012	1,000
Year ending December 31, 2013	900
Year ending December 31, 2014	900
Year ending December 31, 2015	800
Year ending December 31, 2016	800
Mortgage Service Rights
Estimated future amortization expense
Year ending December 31, 2012	18,600
Year ending December 31, 2013	13,800
Year ending December 31, 2014	10,000
Year ending December 31, 2015	7,400
Year ending December 31, 2016	$ 5,700

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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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