Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2025	Sep. 30, 2024
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Respirator reserve	$ 34	$ 35

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