Business Segments - Segment Operating Results (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Product Liability Contingency [Line Items]
Net provisions for litigations and regulatory proceedings	$ 256	$ 3,400

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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