Loan Servicing Servicing Asset Valuation Inputs (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Servicing Asset [Abstract]
Weighted average prepayment	18.30%	19.40%
Weighted average discount rate	10.10%	10.20%

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration