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v3.23.2

Debt and Other Obligations Lease/Leaseback Obligations (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 30, 2023 USD ($) | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Sep. 30, 2053 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2022
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
CT and QTE outstanding leaseback obligation | $ 0 |  | $ 0 |  |  |
Leasing transaction, number of units |  |  |  |  |  | 16
Leasing transaction, number of units |  |  |  |  |  | 16
CT and QTE outstanding leaseback obligation | 0 |  | 0 |  |  |
Lagoon Creek |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
Amortization of reacquired rights | 2 |  |  |  |  |
Lagoon Creek | Forecast |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
Amortization of reacquired rights |  | $ 1 |  | $ 2 | $ 5 |
Kemper/Lagoon Creek leasehold interests |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
leasehold interest | 155 |  |  |  |  |
leasehold interest | $ 155 |  |  |  |  |
Lagoon Creek |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
leasehold interest |  |  | 78 |  |  |
leasehold interest |  |  | 78 |  |  |
Kemper |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
leasehold interest |  |  | 77 |  |  |
leasehold interest |  |  | $ 77 |  |  |
Kemper/Lagoon Creek leasehold interests |  |  |  |  |  |
Sale Leaseback Transaction [Line Items] |  |  |  |  |  |
Leasing transaction, number of units |  |  |  |  |  | 8
Leasing transaction, number of units |  |  |  |  |  | 8

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- Definition The outstanding leaseback obligations related to combustion turbine units and qualified technological equipment and software. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 840 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481295/840-40-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479741/842-40-50-2 + Details
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