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Investments (Aggregated Balance Sheet Summarized Financial Information for Partnerships in our Alternative Investment Portfolio) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Assets	$ 128,158	$ 112,232
Equity Method Investment, Nonconsolidated Investee, Other
Partner's capital	112,694	99,861
Investments Accounted For Under The Equity Method [Member]
Investments	114,038	107,347
Liabilities	$ 15,464	$ 12,371

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

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