Segment Information - Reconciliation of Operating Revenues (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 34,440	$ 33,485
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	33,872	32,904
Corporate and other
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	647	660
Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ (79)	$ (79)

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