Commitments and Contingencies (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011
Financing Receivable Recorded Investment [Line Items]
Financing receivables, purchases during the period	$ 18.5	$ 84.5
Financing receivables, sales during the period	0	0
Performing [Member]
Financing Receivable Recorded Investment [Line Items]
Financing receivable	100.2	100.2
Performing [Member] \| Commercial Real Estate Other Receivable [Member]
Financing Receivable Recorded Investment [Line Items]
Financing receivable	43.3	43.3
Performing [Member] \| Residential Prime Financing Receivable [Member]
Financing Receivable Recorded Investment [Line Items]
Financing receivable	56.9	56.9
Nonperforming [Member]
Financing Receivable Recorded Investment [Line Items]
Financing receivable	$ 0	$ 0

The amount of the recorded investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, accounts receivable (with terms exceeding one year), notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Receivable

-URI http://asc.fasb.org/extlink&oid=6953735

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of any significant purchases of financing receivables during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (e)

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Balance Type:	debit
Period Type:	duration

- Definition

The amount of any significant sales of financing receivables during the reporting period.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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