Goodwill, Core Deposit Premium and Other Intangible Assets (Estimated future amortization expense for amortizable intangible assets) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2013	$ 4,339
Year ending December 31, 2014	5,734
Year ending December 31, 2015	4,488
Year ending December 31, 2016	3,413
Year ending December 31, 2017	2,341
Year ending December 31, 2018	1,271
Thereafter	470
Core Deposits [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2013	366
Year ending December 31, 2014	468
Year ending December 31, 2015	267
Year ending December 31, 2016	238
Year ending December 31, 2017	212
Year ending December 31, 2018	187
Thereafter	228
Mortgage Servicing Rights [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2013	3,951
Year ending December 31, 2014	5,223
Year ending December 31, 2015	4,179
Year ending December 31, 2016	3,134
Year ending December 31, 2017	2,089
Year ending December 31, 2018	1,045
Thereafter	0
Customer Relationships [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2013	22
Year ending December 31, 2014	43
Year ending December 31, 2015	42
Year ending December 31, 2016	41
Year ending December 31, 2017	40
Year ending December 31, 2018	39
Thereafter	$ 242

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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.

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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 in the remainder of the fiscal year following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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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

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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

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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

+ Details

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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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