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Investments (Aggregated Balance Sheet Summarized Financial Information for Partnerships in our Alternative Investment Portfolio) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Assets	$ 112,232	$ 58,819
Equity Method Investment, Nonconsolidated Investee, Other
Partner's capital	99,861	52,075
Investments Accounted For Under The Equity Method [Member]
Investments	107,347	55,145
Liabilities	$ 12,371	$ 6,744

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

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