Securitization Activities and Variable Interest Entities (Details 3) (Variable Interest Entity Not Primary Beneficiary [Member], USD $) In Millions	Aug. 31, 2011	Nov. 30, 2010
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	$ 103,076.8	$ 101,512.0
Maximum exposure to loss in non-consolidated VIEs	3,118.3	2,877.4
Carrying Amount	3,050.8	2,796.1
Collateralized loan obligations [Member]
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	1,794.1	1,937.8
Maximum exposure to loss in non-consolidated VIEs	45.5	35.3
Carrying Amount	45.5	35.3
Mortgage- and asset-backed vehicles - Non-agency [Member]
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	92,722.8	91,285.1
Maximum exposure to loss in non-consolidated VIEs	847.6	852.1
Carrying Amount	847.6	852.1
Mortgage- and asset-backed vehicles - Agency [Member]
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	7,296.5	7,464.8
Maximum exposure to loss in non-consolidated VIEs	2,090.7	1,840.9
Carrying Amount	2,090.7	1,840.9
Asset management vehicle [Member]
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	1,167.1	760.4
Maximum exposure to loss in non-consolidated VIEs	3.0	18.1
Carrying Amount	3.0	18.1
Private equity vehicles [Member]
Total assets, maximum exposure to loss and carrying amount of interests in non consolidated VIE
VIE Assets	96.3	63.9
Maximum exposure to loss in non-consolidated VIEs	131.5	131.0
Carrying Amount	$ 64.0	$ 49.7

AssetsMaximumExposureToLossAndCarryingAmountOfInterestsInNonConsolidatedVieAbstract.

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- Definition

Total amount of assets on the balance sheet or total deal size of unconsolidated vehicles in which the company has exposure to loss as of the balance sheet date.

+ Details

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

- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=6970148&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4/FIN46(R)
-Paragraph C6
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6970148&loc=d3e5747-111685

+ Details

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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).

+ References

+ Details

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