Mortgage Servicing Rights (Key assumptions) (Details) (Mortgage Servicing Rights)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Mortgage Servicing Rights
Key data and assumptions used in estimating the fair value of mortgage servicing rights
Weighted-Average Constant Prepayment Rate (as a percent)	12.96%	11.62%
Weighted-Average Life (in years)	5 years 9 months 28 days	6 years 3 months 12 days
Weighted-Average Note Rate (as a percent)	4.27%	4.28%
Weighted-Average Discount Rate (as a percent)	10.32%	10.61%

The weighted average note rate of securitized assets. This is used as a key input in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement, if any, as of the date of the latest statement of financial position presented.

No definition available.

+ Details

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- Definition

Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

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