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Leases, SoCF (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Lessee, Lease, Description [Line Items] |  |  |
Operating cash flows for operating leases | $ 72 | $ 78 | $ 77
Operating cash flows for finance leases | 46 | 37 | 43
Financing cash flows for finance leases | 82 | 76 | 56
Lease assets obtained in exchange for lease obligations - finance | 28 | 230 | 3
Lease assets obtained in exchange for lease obligations - operating | $ 14 | $ 115 | $ 84

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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://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/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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