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Investments (Aggregated Balance Sheet Summarized Financial Information for Partnerhips in our Alternative Investment Portfolio) (Details) (Details) (Investments Accounted For Under The Equity Method [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Investments Accounted For Under The Equity Method [Member]
Investments	$ 11,020	$ 12,214
Total assets	11,727	12,912
Total liabilities	573	657
Partners' capital	$ 11,154	$ 12,255

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The amount of investments reported by an equity method investment of the entity.

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