Pension and Other Benefit Programs - Estimated Future Benefit Payments (Parenthetical) (Detail) $ in Millions	Sep. 30, 2023 USD ($)
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Expected Medicare subsidy receipts	$ 39

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.

No definition available.

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