Guarantees and Contingencies (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	9 Months Ended
Apr. 30, 2011	Jul. 31, 2009 Issuers	Sep. 30, 2011
Guarantees and Contingencies
Number of issuers of private placement interests sold by the Company's subsidiary subject of SEC actions		2
Payment under settlement agreements	$ 150
Damages sought by plaintiffs			$ 20

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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