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v3.25.3

Commitments and Contingencies - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Loss Contingencies [Line Items] |  |  |
Raw material purchased | $ 262,000,000 | $ 280,000,000 | $ 370,000,000
Accounts payable and accrued liabilities | 8,000,000 | 12,000,000 |
Reserved for environmental matters | 5,000,000 | 5,000,000 |
Charges for environmental expense | $ 1,000,000 | $ 1,000,000 | $ 1,000,000
Environmental Remediation Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] | Cost of sales | Cost of sales | Cost of sales
Cash payments for environmental reserves | $ 1,000,000 | $ 1,000,000 | $ 1,000,000
Settlement amount | 2,000,000 | 3,000,000 | 9,000,000
Indirect tax settlement charges | 7,000,000 |  |
(Provision) benefit for income taxes | (196,000,000) | (111,000,000) | 28,000,000
Respirator Liabilities [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Respirator reserve and defense costs | 33,000,000 | 35,000,000 |
Respirator Liabilities [Member] | Selling and Administrative Expenses [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Respirator charge | 0 | 0 | 8,000,000
Per Accident for Auto [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Self-insured liability | 500,000 |  |
Per Occurrence for All Other [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Self-insured liability | 2,000,000 |  |
Per Accident for U.S. Workers' Compensation [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Self-insured liability | 1,000,000 |  |
Maximum [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Retention for medical costs per person per annum | 300,000 |  |
Non-Controlling Interests [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Raw material purchased | $ 124,000,000 | $ 138,000,000 | $ 192,000,000

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