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v3.23.1

Regulatory Assets and Liabilities (Details) $ in Millions | Mar. 31, 2023 USD ($) Units | Sep. 30, 2022 USD ($) Units
--- | --- | ---
Regulatory Assets and Liabilities |  |
Current regulatory assets | $ 328 | $ 138
Non-current regulatory assets | 5,820 | 6,134
Regulatory assets | 6,148 | 6,272
Current regulatory liabilities | 244 | 391
Regulatory Liability, Noncurrent | 68 | 172
Regulatory Liabilities | $ 312 | $ 563
Power Purchase Agreement with Option to Settle |  |
Regulatory Assets and Liabilities |  |
Number of contracts | Units | 1 | 0
Derivative, Nonmonetary Notional Amount | 342 | 0
Fair value | $ (12) | $ 0
Fuel cost adjustment tax equivalents |  |
Regulatory Assets and Liabilities |  |
Current regulatory liabilities | 216 | 218
Fuel cost adjustment receivable/liability |  |
Regulatory Assets and Liabilities |  |
Current regulatory liabilities | 3 | 0
Unrealized gains/losses on commodity derivatives |  |
Regulatory Assets and Liabilities |  |
Current regulatory liabilities | 25 | 173
Regulatory Liability, Noncurrent | 6 | 102
Postretirement Benefit Costs |  |
Regulatory Assets and Liabilities |  |
Regulatory Liability, Noncurrent | 62 | 70
Unrealized losses on interest rate derivatives [Member] |  |
Regulatory Assets and Liabilities |  |
Current regulatory assets | 41 | 47
Non-current regulatory assets | 544 | 479
Unrealized gains/losses on commodity derivatives |  |
Regulatory Assets and Liabilities |  |
Current regulatory assets | 249 | 14
Non-current regulatory assets | 46 | 1
Fuel cost adjustment receivable/liability |  |
Regulatory Assets and Liabilities |  |
Current regulatory assets | 38 | 77
Pension Costs [Member] |  |
Regulatory Assets and Liabilities |  |
Non-current regulatory assets | 1,776 | 1,839
Nuclear desommissioning costs [Member] |  |
Regulatory Assets and Liabilities |  |
Non-current regulatory assets | 631 | 821
Non-nuclear decommissioning [Member] |  |
Regulatory Assets and Liabilities |  |
Non-current regulatory assets | 2,688 | 2,856
Other non-current regulatory assets [Member] |  |
Regulatory Assets and Liabilities |  |
Non-current regulatory assets | $ 135 | $ 138

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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 + Details
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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