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v3.22.2.2

Fair Value Measurements - Investments (Details) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2022 USD ($) Units | Sep. 30, 2021 USD ($)
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Long-term Investments | $ 3,671 | $ 4,053
Balance in the NDT | 2,500 |
Balance in the ART | $ 1,100 |
Period of time where the investor contributes capital to an investment in a private partnership - minimum | Units | 3 |
Period of time where the investor contributes capital to an investment in a private partnership - maximum | Units | 4 |
Minimum investment period | 10 years |
Fair value of gross plan assets | $ 8,566 | 9,749
Number of readily available quoted exchange prices for the investments | 0 |
LTDCP |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Unrealized gains (losses) on investments | $ (5) | 1
SERP |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Unrealized gains (losses) on investments | (19) | 7
ART |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Unrealized gains (losses) on investments | (190) | 145
NDT |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Unrealized gains (losses) on investments | (396) | $ 279
Equity Funds [Member] |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Commitments, Fair Value Disclosure | 187 |
Real Estate Funds [Member] |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Commitments, Fair Value Disclosure | 128 |
Credit [Member] |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Commitments, Fair Value Disclosure | 57 |
Defensive growth assets |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Commitments, Fair Value Disclosure | 104 |
Private real estate funds |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Fair value of gross plan assets | 75 |
Private Credit [Member] |  |
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items] |  |
Commitments, Fair Value Disclosure | $ 32 |

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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. This amount is not reduced by non-benefit liabilities. + References No definition available. + Details
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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning nuclear facilities. + References No definition available. + Details
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