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, 2012
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2012	$ 2,984
Year ending December 31, 2013	3,842
Year ending December 31, 2014	2,927
Year ending December 31, 2015	2,082
Year ending December 31, 2016	1,405
Year ending December 31, 2017	727
Thereafter	328
Core Deposits [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2012	223
Year ending December 31, 2013	423
Year ending December 31, 2014	184
Year ending December 31, 2015	15
Year ending December 31, 2016	14
Year ending December 31, 2017	12
Thereafter	52
Servicing Contracts [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2012	2,740
Year ending December 31, 2013	3,374
Year ending December 31, 2014	2,700
Year ending December 31, 2015	2,025
Year ending December 31, 2016	1,350
Year ending December 31, 2017	675
Thereafter	0
Customer Relationships [Member]
Future amortization expense for amortizable intangible assets [Line Items]
Six months ending December 31, 2012	21
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	$ 276

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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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