Variable Interest Entities Narrative (Details) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Variable Interest Entities [Abstract]
Consolidated variable interest entities aggregate assets	$ 51,000,000	$ 27,100,000
Consolidated variable interest entities aggregate liabilities	18,700,000	200,000
Redeemable noncontrolling interests in subsidiaries	519,000	1,543,000
Collateralized debt obligations unconsolidated VIE assets	2,000,000	12,800,000
Collateralized debt obligations original expected maturity, years	12
Variable interest in CDO, equity interest limit, maximum	25.00%
Ownership interest in equity-method investment	12.00%
Assets under management of equity investee	800,000,000
Deconsolidated variable interest entities redeemable noncontrolling interest in subsidiaries	7,600,000	21,300,000
Deconsolidated variable interest entities investments	$ 17,700,000	$ 22,000,000

Collateralized debt obligations original expected maturity.

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- Definition

The decrease in Redeemable noncontrolling interest in subsidiaries attributable to the deconsolidation of certain variable interest entities during the period

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- Definition

The amount of assets being managed at the reporting date by the equity method investee.

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- Definition

Variable Interest Entities [Abstract]

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- Definition

The decrease in Investments attributable to the deconsolidation of certain variable interest entities during the period.

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- Definition

Variable interest in CDO, equity interest limit, maximum

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

The fair value as of the reporting date of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) is represented by an equity interest that does not conform to either common or preferred equity (noncontrolling) interests otherwise provided for in the taxonomy, regardless of investee entity legal form.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Subparagraph (12)(c)

-Section S99

-Paragraph 3A

-URI http://asc.fasb.org/extlink&oid=6802392&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Subparagraph 14

-Paragraph 3A

-Section S99

-URI http://asc.fasb.org/extlink&oid=6802392&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number D-98

-Paragraph 43

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Subparagraph 15

-Paragraph 3A

-Section S99

-URI http://asc.fasb.org/extlink&oid=6802392&loc=SL6540498-122764

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number D-98

-Paragraph 43

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 27

-Appendix A

-Subparagraph c

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Subparagraph (16)(c)

-Paragraph 3A

-Section S99

-URI http://asc.fasb.org/extlink&oid=6802392&loc=SL6540498-122764

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

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- Definition

The carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE).

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

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-Paragraph 4

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