Goodwill, Core Deposit Intangibles and Other Intangible Assets (Estimated Future Amortization Expense for Amortizable Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Future amortization expense for amortizable intangible assets [Line Items]
Year ending December 31, 2013	$ 6,005
Year ending December 31, 2014	4,685
Year ending December 31, 2015	3,440
Year ending December 31, 2016	2,366
Year ending December 31, 2017	1,295
Thereafter	695
Core Deposit Intangibles
Future amortization expense for amortizable intangible assets [Line Items]
Year ending December 31, 2013	742
Year ending December 31, 2014	468
Year ending December 31, 2015	267
Year ending December 31, 2016	238
Year ending December 31, 2017	212
Thereafter	414
Mortgage Servicing Rights
Future amortization expense for amortizable intangible assets [Line Items]
Year ending December 31, 2013	5,218
Year ending December 31, 2014	4,174
Year ending December 31, 2015	3,131
Year ending December 31, 2016	2,087
Year ending December 31, 2017	1,043
Thereafter	0
Customer Relationship Intangible
Future amortization expense for amortizable intangible assets [Line Items]
Year ending December 31, 2013	45
Year ending December 31, 2014	43
Year ending December 31, 2015	42
Year ending December 31, 2016	41
Year ending December 31, 2017	40
Thereafter	$ 281

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Amount of amortization expense expected to be recognized after the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: 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=7658586&loc=d3e16323-109275

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- Definition

Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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