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Subsequent Events (Details) - USD ($) $ in Millions | Nov. 14, 2022 | Sep. 30, 2022 | Sep. 30, 2021
--- | --- | --- | ---
Debt Instrument, Redemption [Line Items] |  |  |
Non-current regulatory liabilities |  | $ 172 | $ 40
Regulatory assets |  | 6,134 | 7,956
Unrealized gains/losses on commodity derivatives |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Non-current regulatory liabilities |  | $ 102 | $ 40
Scenario, Forecast |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Increase/Decrease in Interest Rate Swap Liability | $ 120 |  |
Scenario, Forecast | Unrealized gains/losses on commodity derivatives |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Regulatory assets | 2 |  |
Scenario, Forecast | DeferredDerivativeGainLossUnderFHP |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Regulatory assets | 27 |  |
Scenario, Forecast | Unrealized gains/losses on commodity derivatives |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Non-current regulatory liabilities | 48 |  |
Scenario, Forecast | DeferredDerivativeGainLossUnderFHP |  |  |
Debt Instrument, Redemption [Line Items] |  |  |
Non-current regulatory liabilities | $ 50 |  |

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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + 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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