Segment Information - Reconciliation of Operating Revenues (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Operating revenues	$ 34,253	$ 34,504	$ 68,693	$ 67,989
Operating Segments
Segment Reporting [Line Items]
Operating revenues	33,397	33,621	66,980	66,241
Corporate and other
Segment Reporting [Line Items]
Operating revenues	936	965	1,872	1,909
Eliminations
Segment Reporting [Line Items]
Operating revenues	$ (80)	$ (82)	$ (159)	$ (161)

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

- 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.

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+ Details