Mortgage Servicing Rights (Amortization method rollforward) (Details) (Mortgage Servicing Rights, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Mortgage Servicing Rights
Change in Carrying Value of Mortgage Servicing Rights Accounted for Under the Amortization Method
Balance at Beginning of Period	$ 22,091	$ 24,297
Servicing Rights that Resulted From Asset Transfers	134	354
Amortization	(839)	(654)
Valuation Allowance Provision	(20)	0
Balance at End of Period	21,366	23,997
Valuation Allowance for Impairment of Mortgage Servicing Rights Accounted for under the Amortization Method [Roll Forward]
Balance at Beginning of Period	(57)	0
Valuation Allowance Provision	(20)	0
Balance at End of Period	(77)	0
Fair Value of Mortgage Servicing Rights Accounted for Under the Amortization Method
Beginning of Period	22,837	30,100
End of Period	$ 21,431	$ 28,303

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

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-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 50

-Section 50

-Paragraph 4

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-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

+ Details

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Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

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-Publisher FASB

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=7516967&loc=d3e66267-113978

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Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

+ Details

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New provisions recoveries or charged against this account which increase or reduce the net value of servicing assets.

+ References

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