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Investments (Aggregated Balance Sheet Summarized Financial Information for Partnerships in our Alternative Investment Portfolio) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Assets	$ 58,819	$ 45,432
Equity Method Investment, Nonconsolidated Investee, Other
Partner's capital	52,075	39,762
Investments Accounted For Under The Equity Method [Member]
Investments	55,145	43,857
Liabilities	$ 6,744	$ 5,670

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

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