Mortgage Servicing Rights Mortgage Servicing Rights (Economic Assumptions) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2015 Rate	Dec. 31, 2014 Rate
Servicing Asset Key Economic Assumptions [Line Items]
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Prepayment Speed	16.07%	14.25%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost to Service Loans	56,020.00	56,020.00
Conventional fixed loans
Servicing Asset Key Economic Assumptions [Line Items]
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate	6.95%	7.20%
All loans excluding conventional fixed loans
Servicing Asset Key Economic Assumptions [Line Items]
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate	8.95%	9.20%

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Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost to Service Loans

+ References

No definition available.

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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