Litigation, Claims and Contingencies - Summary of Reconciliation of Changes in Environmental Remediation Reserves (Parenthetical) (Details) - USD ($) $ in Millions	Jun. 30, 2026	Sep. 30, 2025
Loss Contingencies [Line Items]
Enivronmental remediation reserves included within other noncurrent liabilities	$ 184	$ 179

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.

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+ Details