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Investments (Aggregated Balance Sheet Summarized Financial Information for Partnerships in our Alternative Investment Portfolio) (Details) - Investments Accounted For Under The Equity Method [Member] - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Investments	$ 11,244	$ 7,527
Total assets	12,075	8,515
Total liabilities	1,802	316
Partners' capital	$ 10,273	$ 8,199

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

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