Litigation, Claims and Contingencies - Summary of Reconciliation of Changes in Environmental Remediation Reserves (Details) - USD ($) $ in Millions |
9 Months Ended | |
|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Loss Contingencies [Line Items] | ||
| Reserve - beginning of period | $ 221 | $ 214 |
| Disbursements | (29) | (34) |
| Revised obligation estimates and accretion | 50 | 51 |
| Reserve - end of period | $ 242 | $ 231 |
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash outflow to settle environmental loss contingencies. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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