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v3.25.3

Leases (Details) | 12 Months Ended
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Sep. 30, 2025 USD ($) Units | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($)
Lessee, Lease, Description [Line Items] |  |  |
Operating Lease, Right-of-Use Asset | $ 113,000,000 | $ 149,000,000 |
Finance Lease, Right-of-Use-Asset, after Accumulated Amortization | 663,000,000 | 729,000,000 |
Total lease assets | 776,000,000 | 878,000,000 |
Operating Lease Liability Current | 46,000,000 | 63,000,000 |
Current Finance Lease Liability | $ 86,000,000 | $ 80,000,000 |
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Other long-term liabilities | Other long-term liabilities |
Total lease liabilities | $ 835,000,000 | $ 931,000,000 |
Operating Lease, Cost | 73,000,000 | 77,000,000 | $ 69,000,000
Variable Lease, Cost | 337,000,000 | 258,000,000 | 134,000,000
Short-term Lease, Cost | 15,000,000 | 10,000,000 | 18,000,000
Finance Lease, Right-of-Use Asset, Amortization | 91,000,000 | 79,000,000 | 57,000,000
Finance Lease, Interest Expense | 46,000,000 | 37,000,000 | 43,000,000
Total finance lease costs | 137,000,000 | 116,000,000 | 100,000,000
Lease, Cost | 562,000,000 | 461,000,000 | $ 321,000,000
Operating lease under PPA | 75,000,000 | 121,000,000 |
Finance Lease, Liability, Noncurrent | 640,000,000 | 700,000,000 |
Leases |  |  |
Finance lease under PPA | 509,000,000 | $ 550,000,000 |
Expected Capacity Payments - PPA Leases | $ 862,000,000 |  |
Number of PPAs for solar generation and discharge battery energy storage system | Units | 3 |  |
Lessee, Finance Lease, Remaining Lease Term | 21 years |  |

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- Definition Finance Lease, Right-of-Use-Asset, after Accumulated Amortization + References No definition available. + Details
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- Definition Amount of amortization expense attributable to right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479041/842-20-45-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-4 + Details
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- Definition Remaining lease term of finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-4 + Details
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