Basis of Presentation and Summary of Significant Accounting Policies (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Unconsolidated Subsidiaries
Financial Policies of subsidiaries including certain entities ownership (as a percent)	20.00%
Portfolio Assets
Carrying value of purchased credit-impaired loans accounted for under the cost-recovery method	$ 18.3	$ 22.1
Carrying value of purchased credit-impaired loans accounted for under the cash basis method	$ 16.5	$ 17.6

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7880789&loc=SL6759159-111685

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Balance Type:	na
Period Type:	duration