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v3.25.3

Other Long-Term Liabilities Other Long-Term Liabilities (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Other Long-Term Liabilities |  |  |
Interest rate swaps | $ 698 | $ 840 |
Currency swap liabilities | 115 | 116 | [1]
Operating Lease, Liability, Noncurrent | 63 | 88 |
Derivative, Fair Value, Net [Abstract] |  |  |
EnergyRight financing obligation | (74) | (74) |
Deferred Revenue, Noncurrent | 39 | 48 |
Non-current regulatory liabilities | 141 | 83 |
Total other long-term liabilities | 1,606 | 1,712 |
Finance Lease, Liability | 726 |  |
Deferred Compensation Liability, Current | (70) | (74) |
Current portion of energy prepayment obligations | 25 | 28 |
Fair value | 12 | 64 |
Long-term debt of variable interest entities (including current maturities) | 1,696 | 966 |
Long-term project cost accruals | 204 | 140 |
Environmental Exit Costs, Costs Accrued to Date | 274 | 226 |
Deferred Compensation Liability, Classified, Noncurrent | 54 | 50 |
Other Sundry Liabilities | 21 |  |
Environmental Remediation |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Environmental Exit Costs, Costs Accrued to Date |  | 14 |
Other long-term liabilities |  |  |
Other Long-Term Liabilities |  |  |
Interest rate swaps | 643 | 792 |
Currency swap liabilities | 108 | 109 |
Derivative, Fair Value, Net [Abstract] |  |  |
EnergyRight financing obligation | (53) | (52) |
Customer Advances for Construction | 61 | 55 |
Membership interests of VIE subject to mandatory redemption | 25 | 7 |
Other | 70 | 81 |
Accounts payable and accrued liabilities |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
EnergyRight financing obligation | (13) | (13) |
Customer Advances for Construction | 155 | 60 |
Long-term project cost accruals | 256 |  |
Environmental Exit Costs, Costs Accrued to Date | 52 | 3 |
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount, Current | $ 17 | 16 |
Accounts Payable [Member] |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Long-term project cost accruals |  | $ 124 |
[1] | See Note 16 — Risk Management Activities and Derivative Transactions — Offsetting of Derivative Assets and Liabilities.

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